BY:N.C. Department of Environment and Natural ResourcesDivision of Pollution Prevention and Enviornmental AssistanceDivision of Water ResourcesLand-of-Sky Regional Council, Waste Reduction Partners

WaterEfficiencyManual

WaterEfficiencyManual

for Commercial, Industrialand Institutional Facilities

for Commercial, Industrialand Institutional Facilities

A joint publication of the Division of Pollution Prevention and Environmental Assistance and Division of WaterResources of the N.C. Department of Environment and Natural Resources, and Land-of-Sky Regional Council.

May 2009

The information contained in this publication is believed to be accurate and reliable. However, the application ofthis information is at the reader’s own risk. Mention of products, services or vendors in the publication does notconstitute an endorsement by the state of North Carolina, nor the Land-of-Sky Regional Council. The informationcontained in this publication may be cited freely.

State of North CarolinaBeverly Eaves Perdue, GovernorDee Freeman, Secretary of the Department of Environment and Natural ResourcesGary Hunt, Director of the Division of Pollution Prevention and Environmental AssistanceTom Reeder, Director of the Division of Water Resources

WaterEfficiencyManual

When to Use This Guide

Now, to determine what you can do to reduce water use, improve efficiencyand save money in your operation.

As you plan and budget for next year, to determine what programs,equipment and employee participation will be necessary to use water moreefficiently.

Before you purchase any new water-using domestic fixtures,cooling, heating, processing, landscaping and facility support equipmentand service contracts.

Before you seek buy-in and support from your management,maintenance and production personnel. They also should read thismanual.

Before any facility upgrading, new construction, processingexpansions and new product manufacturing.

During unforeseeable water shortages, drought conditions orvoluntary/mandatory water conservation requirements.

Contents1 Reasons for Water Efficiency Efforts........................................................ 5

Sound Principles of Water Management ............................................... 10

Conducting a Successful Water Efficiency Program .............................. 17

Water Management Options .................................................................. 27Sanitary/Domestic Uses ................................................................................ 27Cooling and Heating ..................................................................................... 39Boilers ............................................................................................................. 49Kitchen and Food Preparation ...................................................................... 53Commercial Laundries .................................................................................. 59Cleaning, Rinsing and In-process Reuse ....................................................... 61Reuse and Reclamation ................................................................................. 66Landscaping ................................................................................................... 70

Industry-Specific Processes ..................................................................... 82Textiles ............................................................................................................ 82Food & Beverage ............................................................................................ 90Metal Finishing ............................................................................................ 100

Auditing Methodology and Tools ......................................................... 106

Drought Contingency Planning for Facility Managers .........................117

Definitions, Resources & References ................................................... 122

234

876

5

AcknowledgmentsThe N.C. Department of Environment and Natural Resources would like to acknowledge thefollowing people and organizations that have contributed to the development, review andprinting of this manual.

N.C. Division of Pollution Prevention and Environmental AssistanceChris FrazierSarah GrantLeigh JohnsonKeyes McGeeClaudia Powell

Waste Reduction PartnersTerry AlbrechtThomas EdgertonDon HollisterTom Kimmell

N.C. Division of Water ResourcesDon Rayno

Mauri Galey, Nalco, Burlington, North CarolinaJames Manning, Fluidyne International, Asheville, North CarolinaDr. Charles Peacock, N.C. State University, College of Agriculture and Life Science,

RaleighDr. John Rushing, N.C. State University, College of Agriculture and Life Science, RaleighDr. Brent Smith, N.C. State University, College of Textiles, Raleigh

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Chapter 1

1 Reasons for WaterEfficiency Efforts

North Carolina is generally con-sidered to have abundant water resources.However, water resources are becoming amajor concern in North Carolina.

The state’s rapidly growing population hasincreased the demand for water and thestate’s recent drought conditions have causedmany public water supply systems to experi-ence limited availability of raw water.

From 1990 to 2007, statewide population in-creased by approximately 38 percent from 6.6million to 9.1 million. This trend is expectedto continue with the state’s population pro-jected to grow to 12 million by 2030.

Using water more efficiently will be a majorpart of the solution to the state’s water di-lemma. By using water more efficiently, ex-isting supplies can be used to meet additionaldemands. Water efficiency programs will help

Water Issues inNorth Carolina

North Carolina meet water re-source challenges of the future.

Surface sources include reser-voirs, lakes, streams and rivers. According tothe U.S. Geological Survey, 94 percent of wa-ter withdrawn in North Carolina for all usesis taken from surface sources.

As the state’s demand for water has increased,development of new water supply reservoirshas not kept up with the rate of demandgrowth. From 1910 to 1965, reservoir storagewas added at the rate of about 1.9 acre-feetfor each new resident. Since 1965, the ratehas decreased to about 0.19 acre-feet per newresident, or one-tenth the rate from 1910 to1965.

Areas within the state are already facing watersupply infrastructure challenges. Some watersystems are experiencing seasonal demand thatapproaches the limits of their available raw wa-ter supply. While some systems are limited bywatershed capacity, especially during low pre-

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Chapter 1

Benefits ofWater Efficiency Programs

Reduced Water DemandGenerally faster, cheaper and easierthan supply-side programs.

Water and WastewaterTreatment SavingReduces costs and defers plant expan-sion.

Less Environmental ImpactDue to fewer surface and subsurfacewithdrawals.

Sustained Water QualityReduces groundwater’s contaminantintrusion and curtails demand for newsupplies that are of lower quality.

Industrial, Commercial andInstitutional Water Use

FIGURE 1-1

Data reported in 2006 and 2007 local water supply plans submitted to the N.C.Division of Water Resources.

cipitation periods, others are limited by inad-equate system capacity to meet peak demands.In many areas the ability to produce additionalpotable water is constrained.

The importance of water for the vitality of thestate cannot be overstated. All consumers mustuse water more efficiently in order to main-tain adequate water availability. Water effi-ciency is a means by which an adequate re-serve water supply capacity can be maintainedin order to make do during cyclical periods ofdrought.

Non-residential users of publicly-supplieddrinking water have a significant impact onpublic water system demand. Informationsubmitted to the Division of Water Resourcesby more than 520 water systems in the mostrecent local water supply plans indicates thatnon-residential users in these systems accountfor about 37 percent of total water use in thesesystems. These systems provide water to about6.6 million people or about 73 percentof the population (see Figure 1-1). ICI wa-ter demand may make up a larger per-centage of total water demand for somepublic water supply systems, dependingon their mix of residential and non-resi-dential customers.

Some ICI facilities withdraw and treatwater from privately owned wells and/orsurface water intakes to supply their ownneeds. Self-supplied users can benefit fromreduced demand from water efficiency im-provements within their facilities by reduc-ing costs and reducing the uncertainty ofraw water availability. Operating a privately-owned water system does not diminish theneed for water efficiency within these ICIfacilities because raw water availability islinked to other users regardless of thesource.

Municipal Water Use in North Carolina

Residential47%

Commercial Use18%

Industrial Use13%

Institutional Use6%

System ProcessWater

8%

Unaccounted-forWater

8%

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Chapter 1

efficiency vs. conservation“Water efficiency” means using improvedtechnologies and practices that deliver equalor better service with less water. Forexample, the use of low-flow faucet aera-tors can be more powerful than no aeratorsfor washing hands. “Water conservation”has been associated with curtailment ofwater use and doing “less” with less water,typically during a water shortage, such as adrought; for example, minimizing lawnwatering and automobile washing in orderto conserve water. Water conservation alsoincludes day-to-day “demand management”to better manage how and when water isused, so it is common to hear the words“water conservation” used synonymouslywith “water efficiency.”

Local and State Responsesto Water Supply IssuesAs a result of increasing water supply demandand the limited quantity of available treatableraw water, public water supply systems areimplementing water efficiency programs.These programs range from including waterefficiency tips in water bills to having special-ized staff available to actively promote andimplement demand management and waterconservation/efficiency programs, as well asto provide customer assistance. Demand-sidemanagement programs are designed to con-trol growth in demand for water to levels thatcan be supported by current PWS system ca-pacity, thus postponing investment in infra-structure or source expansion. These samestrategies can reduce drought-induced detri-mental impacts on water customers. Waterefficiency programs that reduce water demandcan also result in significant savings in waterand wastewater treatment costs (energy, chemi-cals, etc.), thus reducing environmental im-pacts associated with process inputs such aselectricity and chemicals.

Water rates can have a significant impact onthe effectiveness of water efficiency programsand the effects of the programs on the fiscalstability of a water system. Building a success-ful program will require municipalities to aban-don traditional “declining block rate” struc-tures that charge less per unit as users con-sume more. The use of rate structures designedto encourage water conservation, such as “uni-form” and “increasing block” structures, canmake investments in efficiency improvementsmore attractive for water customers. The feasi-bility of capital investments necessary forimplementation of water efficiency optionsdepends largely on the analysis of the expectedpayback period, a key component of which isthe cost of water.

North Carolina requires local governmentsthat supply water to the public and large com-

munity water systems to prepare a local watersupply plan and to update the plan at leastevery five years. Local water supply plans in-clude evaluations of current and future sys-tem demands, current and future raw watersupplies, and an accounting of water use bysector for the reporting year. Preparation ofthese plans provides PWS system managersand community officials the opportunity toevaluate the ability of their water system andsupply sources to meet current and future de-mands.

The N.C. Division of Water Resources is re-sponsible for approving local water supplyplans. As a planning tool, DWR encouragessystems whose average daily demand exceeds80 percent of their available supply to activelymanage growth in water demand, implementa water conservation program and investigateoptions for obtaining additional water sup-plies. Systems with demands in excess of thisthreshold may be susceptible to shortagesduring drought or peak demand periods. Inevaluating options for meeting future de-mand, DWR strongly encourages systems toincorporate ways to use available water sup-plies more efficiently.

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Chapter 1

Tree ring data studies conducted by Jason Ortegren indicate thatNorth Carolina’s climate has alternating cycles of adequate rain anddrought. Currently, the links within this cycle are unpredictable, anddepend greatly on global hemispheric circulation patterns. Informa-tion is still being gathered on the interrelationship between theseglobal patterns. Ortegren discovered, using his models, that overthe past 317 years the occurrences of sustained summer droughts(four or more years) in central portions of North Carolina, SouthCarolina and Georgia have been very prevalent;11, to be exact. In

addition, the frequency of sustained summer droughts increased a lot over time. For ex-ample, five of the 11 occurrences were in the 20th century and the other six were spreadover the previous ~210 years. For the period 1950-2006, the probability of a sustainedsummer drought in a given decade was more than 70 percent. This probability is far higherthan in previous recorded periods. Since the 1980s, North Carolina has experienced droughtsthat lasted a year or two. Given the water resource impacts of one- or two-year droughts,the cumulative effects of sustained summer droughts could be devastating in the absence ofa sound water resources management strategy.

Coordinating EfficiencyEffortsIn light of cyclical drought conditions and rec-ognition of our finite water supply, North Caro-lina is placing a greater emphasis on water effi-ciency as an alternative to developing additionalwater supply sources. Following the 1998-2002drought, the General Assembly charged theEnvironmental Management Commission withdeveloping rules to govern water use duringdroughts. The resulting rules became effectivein March 2007, and can be found in the NorthCarolina Administrative Code as 15A NCAC02E .0600 – Water Use During Droughts andWater Supply Emergencies.

The sudden return of exceptional drought condi-tions again in 2007 and 2008 compelled the gov-ernor and the General Assembly to pass legisla-tion improving drought management, which in-cluded additional water use reporting and require-ments for improved water use efficiency for watersystems applying for state funds for system expan-sions. Session Law 2008-143 reinforces the neces-sity for municipal water systems to develop andimplement a plan for water conservation measures

to respond to droughtor other water short-ages.

Water systems requiredto prepare a local watersupply plan must in-clude a water shortageresponse plan as part of their local plan. Theseplans must be approved by the N.C. Division ofWater Resources. Passage of this legislation pro-vided statutory authority and more specificity tothe requirements for water shortage response planscontained in the drought rules developed in re-sponse to Session Law 2002-167. Water shortageresponse plans must meet the following criteria:

Include tiered levels of water conservationmeasures or other response actions basedon the severity of water shortage conditions.Each tiered level of water conservationmust be based on increased severity ofdrought or water shortage conditionsand will result in more stringent waterconservation measures.All other requirements of rules in ac-cordance with Session Law 2002-167.

Source: Tree-Ring Based Reconstruction of Multi-Year Summer Droughts in Piedmont and Coatal Plain Climate Divisions of theSoutheastern U.S., 1690-2006. Jason A. Ortegren, UNC-Greensboro, 2008.

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Chapter 1

Water Efficiency Demand-Side Programs

Roles and Responsibilitiesin Water Efficiency

The N.C. Department of Environment andNatural Resources may require water systemsto implement more stringent measures in-cluded in their water shortage response planif the system is in:

Severe, extreme or exceptional drought,and the department finds all of the fol-lowing:

The water system has not imple-mented the appropriate level of wa-ter conservation measures as writtenin the water shortage response plan.Implementation of water conserva-tion measures is necessary to mini-mize the harmful impacts of droughton public health, safety and the envi-ronment, including potential impactsof drought or other water shortageon interconnected water systems andother water systems withdrawingfrom the same source of raw water.

Extreme or exceptional drought and thedepartment finds the water system hasalready implemented the appropriatemeasures under the water shortage re-sponse plan for 30 days or more but hasnot reduced water use enough to mini-mize the harmful impacts of drought onpublic health, safety and the environ-ment.

Please note that Session Law 2008-143 doesnot contain any provision that requires me-tering or regulation of withdrawal by privatedrinking water wells.

Across America, water efficiency programs forvarious industrial, commercial and institutionalsectors have been established by various statesand municipal water systems. These programshave achieved much success in cumulative wa-ter savings and have proven to be cost-effectiveto both the public and private sectors. Theseprograms include activities such as on-site au-

When water systems are reaching capacity lim-its of water availability and/or treatment in-frastructure, both public and private sectorshave important roles to play. Comprehensivewater management programs must addressleaks and “unaccounted-for” water use, watershortage planning and water efficiency im-provements, as well as implement customereducation programs and conservation-ori-ented billing structures. Government buildingsand publicly-owned facilities should serve asrole models for water use efficiency in the com-munity.

The private sector can do its part to conserveand use water more efficiently. When indus-trial, commercial and institutional facilities usewater more efficiently, it saves everyone moneywhile also helping to reduce environmentalimpacts.

Many facility managers may view water con-servation measures as actions necessary onlyin droughts, but there are many important rea-sons to continually improve water use effi-ciency. Driving factors include: preservationof the quality of surface and ground water sup-plies; cost avoidance of water and wastewatertreatment by reductions in chemical usage andenergy consumed; and meeting increased fu-ture demands without increased overall wateruse, thus delaying the need for developmentof infrastructure for new raw water suppliesand treatment facilities.

dits, guidebooks, seminars, conservation plan-ning, employee education, advisory committees,trade show expositions, awards, financial incen-tives/assistance, ordinances, regulations, re-search studies and industrial reuse programs.

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Chapter 2

2 Sound Principles ofWater Management

Optimizing facility water use means more than conduct-ing an in-plant study and preparing a report. Water effi-ciency measures must be viewed holistically within abusiness’ strategic planning. Firms that use water moreefficiently now will have a competitive advantage overcompanies that choose to wait. A successful programmust prioritize needs, set well-informed goals, establishcurrent performance minimums and carefully plan acourse for action. Consider these principles when estab-lishing water efficiency initiatives.

Categories of Water Efficiency Measures

Reducing losses (e.g., fixing leaking hose nozzles)Reducing overall water use (e.g., shutting off processwater when not in use)Employing water reuse practices (e.g., reusingwashwater)

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Chapter 2

changing behavior vs. equipmentEquipment changes may be viewed as a “permanent fix” to achieve water efficiency.Changing employee behaviors, such as an operating procedure, may be viewed as a quickand inexpensive way to achieve similar savings without up-front capital expense. In reality,both the technical and human side of water management issues must be addressed. Consis-tent training and awareness in combination with proper tools and equipment will achievemore permanent water savings.

Prioritizing Needs andSetting GoalsBefore considering any water efficiency mea-sure, management must first ensure water useperformance is consistent with:

Public health sanitation requirementssuch as the U.S. Department of Agri-culture, the Food and Drug Adminis-tration and state and local health regu-lations.Environmental requirements such aswater quality reuse rules and criteria.Other health and safety requirements,such as state and local building codesand fire safety codes.Customer quality expectations, such asproduct cleanliness specifications.

Closer examination of the above requirementsmay lead to more water-efficient ways toachieve and exceed health, safety and customerquality requirements. With the above prior-ity established, consider the following sugges-tions before embarking on program goal set-ting.

Any program should include water sup-ply and wastewater utilities in the pro-cess. Involving utilities can help alignwater use goals for both water users andsuppliers. Utilities may have demand-side management concerns such as meet-ing summer’s increased demands or

meeting a peak hourly demand. Thesespecific concerns can be factored into afacility water management program.Anticipate increased water and wastewa-ter service costs when considering op-tions. Ask utilities to provide any ex-pected increases.Anticipate future increases in produc-tion or number of employees that willinfluence water consumption.Use total cost accounting methods toperform economic comparison of water-efficient techniques. Consider water andwastewater costs, on-site pretreatmentcosts, marginal cost for capacity expan-sion and energy savings (especially heat).Encourage water and wastewater utili-ties to provide rebates and other finan-cial incentives to offset the cost of imple-menting a water conservation measure.Use the efficiency/conservation plan asa bargaining point.Program goals should not only considerthe technical side for water efficiency,but also should consider the humanside, such as changing behaviors andattitudes toward water use.Do the simple tasks first to gain accep-tance and positive feedback for the pro-gram.

Use internal and external benchmarking tech-niques to help optimize water consumption.

12

Chapter 2

Typical Water BalanceFindingsUnderstanding water use at a facility is im-perative to appropriately prioritize areas tofocus time and resources. Figures 2-1 through

2-6 show examples of water use distribution(water balances) for common commercial, in-dustrial and institutional settings. Each fa-cility should determine its own unique waterbalance to best target opportunities.

Figure 2-1

Figure 2-2

Figure 2-3

13

Chapter 2

Figure 2-4

Figure 2-5

Figure 2-6

The guidance presented in thischapter provides the framework topursue water efficiency measures.Chapter 3 presents a six-step pro-cess to guide facility staff throughthe details of enacting a successfulwater efficiency program.

14

Chapter 2

Using TQM andBenchmarking ToolsFacility managers have a variety of totalquality management tools to help plan,develop and implement water efficiencymeasures. These tools include self assess-ments, statistical process control, ISO9000 and 14000, process analysis, qual-ity circle and many others. Benchmarking,too, can be an important TQM tool toimprove water use efficiency.Benchmarking is a process of comparingone’s own operational performance toother organization’s to become “best inclass” and make continual improvements.Benchmarking is more than simply setting aperformance reference or comparison, it is a wayto facilitate learning for continual improvements.The key to the learning process is looking out-side one’s own business to other industry sec-tors that have discovered better ways of achiev-ing improved performance. Benchmarking canbe performance-based, process-based or strate-gic-based and can compare financial or opera-tional performance measures, methods or prac-tices or strategic choices.

Five Steps of aBenchmarking ProcessPlanningManagers must select a process to bebenchmarked. A benchmarking team should beformed. The process of benchmarking must bethoroughly understood and documented. Theperformance measure for the process should beestablished (i.e. cost, time and quality).

ObservationThe observation step is a study of thebenchmarking partner’s performance level, pro-cesses and practices that have achieved thoselevels and other enabling factors.

AnalysisIn this phase, comparisons in performance lev-els among the facilities are determined. The rootcauses for the performance gaps are studied. Tomake accurate and appropriate comparisons, thecomparison data must be sorted, controlled forquality and normalized.

AdaptationThis phase is putting what is learned through-out the benchmarking process into action. Thefindings of the benchmarking study must becommunicated to gain acceptance, functionalgoals must be established and a plan must bedeveloped. Progress should be monitored andcorrections in the process made accordingly.

The benchmarking process should be interac-tive. It should also recalibrate performance mea-sures and improve the process itself.

SearchInformation on the “best-in-class” performermust be determined. The information can bederived from the company’s existing network,industry experts, industry and trade associa-tions, publications, public information andother award-winning companies. This infor-mation can be used to identify the best

benchmarking partners with which to begincooperative participation.

Benchmarks(Annual Basis)

Hotels/Motels 0.079 - 0.165 thousand gals. (Kgal)/sq. ft.

30.2 - 39.5 Kgal/room

Nursing/ 0.062 - 0.101 Kgal/sq. ft.

Assisted Living 32.8 - 40.7 Kgal/bed

25.4 - 39.6 Kgal/apartment

Restaurants 0.17 - 0.21 Kgal/sq. ft.

10.6 - 14.3 Kgal/seat

Schools 0.012 - 0.019 Kgal/sq. ft.

1.7 - 2.7 Kgal/studentSource: Benchmarking Task Force Collaboration for Industrial, Commercial &Institutional Water Conservation, Colorado Waterwise Council, June 2007.

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Chapter 2

Self-Assessment Checklist

What efforts has your facility already made in water efficiency? Several questions forfacility managers are listed below to help gauge a facility’s present water efficiencyperformance.

Top Management Commitment and Resources

Is water efficiency included in the company’s environmental policy statement?Are water efficiency responsibilities delegated?Are quantitative goals established and tracked?How are water efficiency goals communicated to employees?What incentives and feedback loops exist for employee participation, suggestions andincreased awareness?Has your facility taken advantage of available help and resources from your utilities,assistance programs, vendors or consultants?

Water Efficiency Survey

Do you know the actual breakdown of your water uses: cooling and heating, domesticuses, process rinsing, cleaning activities, kitchens, laundries, landscaping, watertreatment regeneration, evaporation, leaks and others?Do you know your life cycle water costs for supply water, wastewater treatment,sewer/discharge and heat and mechanical energy losses?Are you doing simple things such as leak inspections, eliminating unnecessary usesand using timers? Are these practices institutionalized?

Identifying Opportunities - Target Areas for Water Reduction

DOMESTIC

Are code-conforming 1.6 gpf commodes, 0.5 to 1.0 gpm faucet aerators and low-flow1.5 to 2.5 gpm showerheads in use?

HEATING/COOLING

Has once-through cooling water used in air conditioners, air compressors, vacuumpumps, etc., been eliminated with the use of chillers, cooling towers or air-cooledequipment?Has blow-down/bleed-off control on boilers and cooling towers been optimized?Is condensate being reused?

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Chapter 2

PROCESS RINSING AND CLEANING

Have you considered improved rinsing techniques such as counter-current systems,sequential use from high quality to lower quality needs, conductivity flow controls,improved spray nozzles/pressure rinsing, fog rinsing or agitated rinsing?Is water turned off when not in use by flow timers, limit switches or manually?Is the life of an aqueous bath being maximized via filtration and maintenance control?Are “dry clean-up” practices used instead of hosing down, and is first-pass pre-cleaning conducted with squeegees, brushes or brooms?

ON-SITE WATER REUSE

Is water quality matched with water quantity?Have reuse applications been examined for process water, landscaping irrigation,ornamental ponds, flush water and cooling towers?

Are low-flow sprinklers, trickle/drip irrigation, optimized watering schedules and waterplacement, preventive maintenance and xeriscaping techniques in place?

LANDSCAPING

KITCHENS

Are “electric eye” sensors for conveyer dishwashers installed?Have new water and energy efficient dishwashers been examined?

Water Efficiency Action Plan

Have you performed a cost analysis on water efficiency opportunities?Do you have a prioritized implementation schedule?Are water users informed of the changes and communication channels open forfeedback?

Tracking and Communicating Results

Do you post monthly water usage rates to employees and management?Are your water efficiency achievements being recognized in case study articles, mediacoverage, mentoring to other businesses, business environmental exchange programsor in award programs?

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Chapter 3

3 Conducting aSuccessful WaterEfficency Program

A successful water efficiency program shouldbegin with a well-thought-out plan. Crucialto the development and use of this plan aremanagement’s commitment; sufficient tech-nical staff and financial resources; employeeawareness and participation; and well-publi-cized results. Water efficiency measures mayvery likely be just one part of an integratedenergy management, pollution prevention orother cost-reduction program or environmen-tal management system. Regardless the driv-

ing factors, a height-ened awareness androad map to water ef-ficiency opportuni-ties and cost savingswill help manage-ment make sound choices to optimize opera-tional efficiency, improve economic competi-tiveness and conserve quality water resourcesfor the future.

Steps for a successful water efficiency program

Step 1 - Establish commitment and goals

Step 2 - Line up support and resources

Step 3 - Conduct a water audit

Step 4 - Identify water management options

Step 5 - Prepare a plan and implementation schedule

Step 6 - Track results and publicize success

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Chapter 3

Line Up Support and ResourcesDesignate a Conservation ManagerA conservation manager, coordinator or teamleader also may have responsibilities for en-ergy management and/or environmentalmanagement. The conservation managershould:

Step 1Establish Commitmentand GoalsAt first, water efficiency goals may be quali-tative and included in statements of commit-ment, environmental policies, budgetaryplanning or other external awareness mea-sures. Initial commit-ments should allo-cate staff and re-sources to assess thecurrent water usebaseline and ex-plore water effi-ciency opportuni-ties. With additional information, realisticgoals of quantitative water efficiency can beestablished. For example, goals could includeestablishing a percent reduction goal in over-all water consumption (such as a 10 percentoverall reduction in water use next fiscal year)or establishing a gallon-per-year reductiongoal in water consumption (such as reducingconsumption by 20,000 gallons per year).Even better goal setting uses industrybenchmarking information based on an op-erating index (such as gallons per pound ofproduct manufactured or gallons consumedper client served). Remember, goal setting isan ongoing process requiring periodic reviewand revisions for continual improvement.

1. Review effectiveness of present water ef-ficiency measures for further improve-ments.

Establish a budget and funding.Evaluate regulatory constraints and lo-cal water supply issues.Seek outside funding, grants and avail-able technical assistance.Coordinate a water efficiency audit.Establish implementation criteria for de-signing water efficiency measures.Develop a plan.Encourage employee participation andcreate awareness.Oversee implementation of efficiencymeasures and activities.Periodically review program progress andmake modifications for continuous im-provement.

2.3.

4.

5.6.

7.8.

9.

10.

Achieve Employee ParticipationThe importance of employee awareness andcooperation in the water conservation pro-gram cannot be overemphasized.

Establish and promote the water effi-ciency/conservation program for em-ployees. Provide background informa-tion about the water conservation policyand its implications for company opera-tions.

Initiate the employee awareness programwith a letter directed to each employeefrom the head of the organization, suchas the CEO, president, owner, mayor,city manager, governor or chief admin-istrator. The letter should describe theestablished conservation policy, identifythe water efficiency coordinator, expressfull support for the plan and invite feed-back.

Emphasize the need for individual re-sponsibility as part of a team effort toachieve efficiency and environmentalgoals.

Establish a “water-saving idea box” andencourage employees at all levels to sub-

Step 2

19

Chapter 3

Communicate WaterConservation Awareness

Incorporate water conservation policiesand procedures into employee trainingprograms.

Use bulletins, e-mail, newsletters, pay-check stuffers or other appropriate meth-ods to transmit policies, programs, ideas,announcements, progress reports andnews of special achievements.

mit water-saving ideas. Respond to eachsuggestion offered.

Schedule staff meetings to communicatethe organization’s water-conservationplan and progress in water savings.

Establish charts that graphically showthe financial savings.

Use audiovisual programs, outsidespeakers and other means for employeemeetings.

Post water-conservation stickers, signsand posters in bathrooms, kitchens, caf-eterias, conference rooms and otherplaces where employees congregate.

Check out thesewater efficiency Web sites

SaveWaterNC.orgwww.savewaternc.org

N.C. Division of Pollution Prevention and Environmental Assistancewww.p2pays.org

N.C. Division of Water Resourceswww.ncwater.org

N.C. Division of Water Qualityhttp://h2o.enr.state.nc.us

N.C. Drought Management Councilwww.ncdroughtcouncil.org

EPA Office of Waterwww.epa.gov/ow

Water Librarian’s Home Pagewww.interleaves.org/~rteeter/waterlib.html

EPA WaterSensewww.epa.gov/watersense

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Chapter 3

Establish Employee IncentivesRecognize and reward those employeeswho submit water-saving ideas.

Include water consumption measures inemployees’ job performance reviews.

Motivate employees by rewarding themwith a percentage of the first year’s di-rect savings.

Allocate water and sewer costs to eachindividual department to create respon-sibility for water efficiency.

Organize and promote competition be-tween shifts.

Use Outside AssistanceOutside organizations are available to assistwith water conservation activities. Assistanceshould be solicited wherever feasible as a re-source for the promotion of water conserva-tion. Some suggestions are listed below.

Take advantage of free or low-cost tech-nical assistance organizations such asEPA’s WaterSense program, N.C. Divi-sion of Pollution Prevention and Envi-ronmental Assistance, N.C. StateUniversity’s Industrial Extension Ser-vice, NCSU’s Industrial AssessmentCenter, Waste Reduction Partners inwestern and central North Carolina, andenergy utilities assistance programs (i.e.,Progress Energy and Duke Energy).

Water and wastewater utilities are vitallyinterested in assisting customers con-serve water. They can provide informa-tion, contacts with other industries andadvice. Water suppliers may even assistcustomers with leak-detection programsor water audits of facilities. Some utili-ties nationwide offer rate reductions and

financial incentives for water efficiencyinvestments.

Participate in any water conservationadvisory group, or similar organization,generally sponsored by local water au-thorities. If such a group does not exist,help the utility establish one.

Consider hiring private consultants tohelp develop water efficiency programsand conduct audits. Ensure profession-als have adequate experience and propercertifications for their field (i.e., certifi-cations for landscaping include certi-fied landscaping irrigation auditors, cer-tified irrigation designers and certifiedirrigation contractors.).

Work with local wastewater utilities andwastewater discharge regulators. As con-servation measures are put into effectin industrial processes, wastewater pol-lutant concentration may increase, al-though the same mass of these pollut-ants have stayed the same. These in-creased concentrations may alter afacility’s ability to meet local, state orfederal effluent discharge limits. Requestwastewater regulators to recognize con-servation efforts by amending the waste-water discharge permits to address totalmass of pollutants instead of concentra-tion levels.

Help Take the Message HomeDevelop an employee education program thatwill encourage employees to save water athome, as well as in the workplace. Some sug-gestions are:

Offer home water-saving devices to em-ployees free or at cost.

Sponsor demonstrations that will edu-cate employees how to water landscapes

[cont’d p. 22]

21

Chapter 3

Chiller

Chiller

HVACParts Cleaningand Rinsing Baths

ProcessMixing and

Vat Cleaning

GeneralWashing and

Sanitation

CoolingTower

Makeup

Boiler HotWater

Make-up

Air CompressorCooling

Once-through

Restroom/DomesticUses

Cafeteria/Food

Preparation

LandscapingUses

OfficeManufacturingArea

WastewaterTreatment

City WaterIN

Process EffluentOUT

DomesticEffluent OUT

EvaporativeLosses

d

e e

e

d

e

e

e

c

c

ee

e

c

d

b

b

b

b

b

e

e

Simplified Water Balanceat a Manufacturing Facility

FIGURE 3-1

Water Balance Summary

Cooling: tower make-up and boiler make-up 7,966,000 38.3

Process use: parts and mixing vat cleaning 3,848,000 18.5

Domestic: faucets, toilets and showers 3,536,000 17

Once-through cooling: air compressors and pumps 2,388,000 11

Landscaping 832,000 4

General washing, sanitation and maintenance 561,600 2.7

Leaks (detected) 416,000 2

Food preparation: dishwasher 312,000 1.5

SUBTOTAL 19,859,000 95.5

TOTAL WATER PURCHASED 20,800,000 100.0

UNACCOUNTED FOR 941,000 4.5

Gallons PercentSources of water use per year of total

22

Chapter 3

Determine the True Cost of Water UseThe true cost of using water may include sev-eral factors other than the actual water util-

Step 3Conduct Water Audit to AssessCurrent Water Uses and CostsTo identify potential water efficiency oppor-tunities, it is first necessary to gain a thor-ough understanding of the site’s water usesthrough a water audit. A water audit is de-fined as the process by which all uses of wa-ter on a site are characterized as to flow rate,flow direction, temperature and quality re-quirements (see Chapter 6).

Water BalanceAn important task is to construct a water bal-ance diagram or summary chart, which iden-tifies all water use from its source throughthe on-site processes, machines, buildings andlandscape irrigation to evaporation and waste-water discharge. To account for all uses inthe water balance, the total inflow shouldequal the total outflow plus irrigation, evapo-ration and other water losses (see Figure 3-1).

Select a Water Audit TeamInclude the following representatives:

Water efficiency coordinatorPersonnel familiar with the operationsFacility management/plant managerMaintenancePossible outside auditors

All sources of potable and non-potablewaterProcess sub-metering dataWastewater treatmentSewer billProduction process sheetPlumbing diagramIrrigation drawing/plan and existingirrigation control programNumber of employeesNumber of shifts, work and clean-upschedulesFacility description – square footage,functionsProducts and services preformed at thesiteProduction rates or client service ratesList of known water-consumingprocesses and usesPrior water use or energy survey(Preventive) maintenance schedules

Walk-Through SurveyThe next step is to conduct a walk-throughsurvey with the audit team. Use direct obser-vation and measurements, and ask questions.Talk with equipment operators who may haveimportant first-hand information. Use thefollowing procedure to conduct the survey.

Identify all water-consuming equipmentConfirm plumbing diagramsQuantify water flow rates and usageDetermine water quality needs for eachprocessReview current water-saving measuresObserve shift clean-ups (third shift), andprocess change-oversAlso note all water losses, evaporativelosses and water incorporated in prod-uct; excessive water pressure; and leaksJudge current water use efficiency andpotential for each operation

efficiently, plant seeds for water-thriftyplants, install low-flow plumbing fix-tures and improve water-use habits. De-vice manufacturers, local hardwarestores or your water utility may be happyto assist with such a program.

Distribute home water conservationbooklets.

Collect Background Site Information andRecords

Water bills (previous full year to threeyears) – note rate structuresWater meter sizes and locations

23

Chapter 3

Process and Equipment Use

Cleaning, washing, rinsing

Metal finishing

Painting

Dyeing and finishing

Photo processing

Reuses

Product fluming (water transport)

Water use in products

Cooling and Heating

Single-pass cooling

Cooling tower/chillers

Boiler, hot water, steam systems

Air washers

Boiler scrubber

Sanitary and Domestic

Toilets

Urinals

Faucets

Showers

Wash-up basins

Kitchen Food

Cafeteria uses

Dishwashers

Ice machines

Faucets

Other Facility Support

Floor washing

Air emission wet scrubbers

Building washing

QA/QC testing

Laboratories

Wastewater treatment

Outdoor Uses

Landscaping

Irrigation

Particulate emission control

Decorative fountains/ponds

Vehicle washing

Personnel

Medical

total cost of water used for aproduction run should be di-vided by the total number ofwidgets produced to get a“cost per widget” of wateruse.

In calculating the total cost of water use andthe many components that go into the totalcost, current prices of all these elements is agood starting point. However, a more mean-

Key areas to check during a walk-through survey

ity fees. Examples of costs include water heat-ing, chemical agents, electrical pumping, on-site pretreatment and related labor (see Figure3-2).

To calculate the dollar savings resulting fromreduced water use, a value for each unit ofwater used must be derived. One approach isto divide the total costs of water used per yearby the total amount of water used. For facili-ties engaged in production of “widgets,” the

24

Chapter 3

City water purchase $2.11Sewer rate $2.43Deionized using reverse osmosis

Equipment $0.41Energy $1.07Labor $1.23

Total deionized water (flexible cost)* $2.71 x 40%Deionized water (flexible cost)* 40% x $2.71 $1.08Wastewater treatment

Sludge disposal $3.78Treatment chemicals $2.64Energy $0.25Labor $6.01

TOTAL wastewater treatment $12.69Wastewater treatment (flexible cost)* 40% x $12.69/CCF $5.07TOTAL cost of water $10.69/CCF

($14.29/1,000 gallons)

When comparing efficiency options, first con-sider reducing consumption of the most ex-pensive components of water use.

ingful comparison can be made using futurerates and prices for these elements after theefficiency measures are put into effect. Thesemajor cost elements include:

Water purchased from utilities. Billingnormally consists of a fixed service costand water rate cost. The fixed chargeshould be excluded from the analysis.Wastewater sewer rate and surcharges.Total cost of on-site water softening ortreatment before use.Cost of energy for heating water.Total cost of pretreating wastewater ef-fluent, including labor, chemical, energy

1.

2.3.

4.5.

and residual disposal.Cost of maintenance personnel per-forming preventive or reactive mainte-nance on water-using components.If water demand is increasing, deter-mine the marginal costs of increasingeffluent treatment capacity.Energy costs for pumping water fromwells or pumping water within the fa-cility itself.

6.

7.

8.

True Cost of WaterExample: Metal Finishing Operation (not heated)

FIGURE 3-2

Estimated savings using total cost of water =250 days/yr x 0.1 x 35,000 gpd x $14.29/1,000 gallons = $12,503/year

If a metal finisher consuming 35,000 gallons per day reduces use by 10 percent, estimated savings usingwater and sewer cost only = 250 days/yr x 0.1 x 35,000 gpd x (2.11/784 + 2.43/784) = $5,310/year

*Flexible cost savings of conserved water estimated to be 40 percent of total treatment cost.

Unit Cost Total Unit Cost ($/CCF)Activity ($/CCF) 1 CCF = 748 gallons

25

Chapter 3

Step 4Identify Water ManagementOpportunities in Plant andEquipmentMany general approaches exist for identify-ing water-saving opportunities. The ap-proaches listed below can be applied to wa-ter uses at any site.

General Approaches forWater-Saving Opportunities

Identify unnecessary uses and fix leaks.Use minimum amounts of water to ac-complish the task.Recirculate water within a process orgroup of processes.Reuse water sequentially.Treat and reclaim used water.Displace potable water supplies withwater from non-potable sources whereappropriate.Install meters at high-flow processes andequipment.Pressure-reducing valves.

This manual provides a detailed discussion aboutwater reduction options in Chapters 4 and 5.

Step 5Prepare a Plan andImplementation ScheduleDevelop an action plan that outlines and listsall proposed water efficiency measures result-ing from the facility audit. Include the fol-lowing items in the plan:

State the company policy regarding con-servation and water efficiency, reflect-ing the commitment of company man-agement.Quantify your goals. Establish theamount of water to be saved through-

Those that are most cost-effectiveand should be put into practice assoon as possible.Those measures that should beevaluated through a trial period tocollect meaningful data.Those measures that are not cost-effective, but could be implementedin times of drought or emergencysituations.

Identify need for any engineering designchanges.Establish the schedule for implement-ing each specific measure.Identify the employee responsible forimplementing each measure; continu-ously monitor the effectiveness and per-formance of each measure.Identify funding sources for specificmeasures that will require capital expen-diture. Consider loans and rebates thatmay be available from energy and waterutilities.Review periodically, and revise plan ap-propriately.

6.

7.

8.

9.

10.

out the entire facility, as well as by eachorganizational unit. Also, set deadlinesby which these savings are to beachieved.Summarize all efficiency measures iden-tified during the water audit and by em-ployee suggestions.Evaluate each of these measures. Be sureto include all costs and benefits includ-ing capital costs, operating costs, pro-jected savings and payback periods. Donot forget to include cost of energy con-sumption, treatment of water, chemicalcosts, creation of solid and toxic wastesand wastewater discharge.Prioritize the measures in the followingorder:

1.

2.

3.

4.

5.

26

Chapter 3

Step 6Track Results andPublicize SuccessPublicize the success of your program. Posi-tive publicity promotes good relations withemployees, the community, other businessesand organizations that support economicdevelopment. It also helps to stimulate simi-lar water management efforts. Some public-ity options include internal memos, companynewsletters, brochures, trade publications,news releases to local media, letters to publicofficials, talk radio and interviews with themedia. Many water utilities will help publi-cize good results to encourage others to de-velop similar plans. A good water efficiencyprogram is news because it means more wa-ter will be available to the community.

Businesses with successful water managementprograms deserve recognition by the public.Likewise, the public should be informed thatbusinesses are socially and environmentallyresponsible partners in the community. Thesesteps can help businesses make their public-ity efforts more visible and successful:

Encourage company conservation teammembers to participate in:

1.

Community conservation seminarsto share program results, as well asobtaining useful information fromother companies’ efforts.Water conservation committeessponsored by local water utilities.

Sponsor water conservation projectssuch as a public xeriscape demonstra-tion garden.Sponsor water conservation contests inschools. For example, encourage stu-dents to create posters to be displayedin the community and at company worksites.

4.

5.

Place posters andother exhibits inpublic buildingsand art fairs.Post signs on wa-ter-thrifty landscapes to identifytypes of plants that require littlewater.Once the plan has shown signifi-cant savings, develop a public rela-tions program, including interviewswith local radio and TV stationsand newspapers, about thecompany’s successes.

2. Present savings in relevant terms suchas dollars, water savings per unit ofproduct, earnings per share or annualconsumption per household.Prepare, display and promote thecompany’s water conservation successesby means such as:

3.

Display the company’s water con-servation results in public receptionareas.

27

Chapter 4

4 Water ManagementOptions

Sanitary/Domestic Uses

Cooling and Heating

Kitchen and Food Preparation

Boilers

Commercial Laundries

Cleaning and Rinsing Applications

Reuse and Reclamation

Landscaping

SANITARY/DOMESTIC USES

Often overlookedare the water andcost savings achiev-able in the domes-tic water usage bycommercial and in-dustrial facilities.While water effi-ciency measures

should begin with the highest water use op-erations such as cooling, cleaning, rinsing,heating, etc., many facilities miss the easy im-provements that can be made in domesticwater devices such as toilets, urinals, sink fau-cets and showers. Domestic water use at in-

dustrial and commercial facilities may rangefrom a few percent at a food processing indus-try to more than 50 percent in an office set-ting. Average daily domestic demands in com-mercial/industrial settings range between 20and 35 gallons per day per employee, and asavings of 25 to 35 percent in this domesticusage is readily achievable.

ToiletsAmericans consume almost 4.8 billion gallonsof water daily by flushing toilets and urinals.In a business office setting, toilet water usagealone can account for approximately one-thirdof all water used. A number of water efficiency

28

Chapter 4

options exist fortoilets in most fa-cilities constructedbefore 1994 thathave not beenrenovated recently.

The three majortypes of toilets in-clude gravity flush,f lush valve andpressurized tanktype. Dual f lushtoilets also are gaining in market share. Pre-1977 gravity toilets will consume five to sevengallons per flush. Pre-1977 flush valve toiletsuse 4.5 to 5.0 gallons per flush. Gravity andflush valve style toilets manufactured between1977 and the mid-1990s mostly use 3.5 gal-lons per flush. High efficiency toilets beganappearing on the market in the mid 2000s.HETs use less than 1.3 gallons per flush.

Code Compliant 1.6Gallons Per Flush Toilet

Pre-1977 5.0-7.0 gpf 4.5-5.0 gpf

1977 to mid 1990s 3.5 (some 5.0 gpf) 3.5 gpf

Mid 1990s 1.6 gpf maximum 1.6 gpf maximum

2003+ best in class 1.3 gpf maximum 1.3 gpf maximum

Typical Water Consumption for ToiletsYearsManufactured Gravity Tank Style Flush Valve Style

FIGURE 4-1

In the 1990s, toilet manufacturers introducedultra-low-flush toilets that use 1.6 gallons perflush. Federal regulations require that all toi-lets manufactured after Jan. 1, 1994, consumeno more than 1.6 gpf. Some of the original

High-Efficiency ToiletsThe most efficient commercial toilet on themarket is the high efficiency toilet. HETs useless than 1.28 gallons per flush. This perfor-mance is achieved by an improved flush andfixture design. Early user satisfaction studiesshow positive customer feedback. HETs com-bine high efficiency with advanced design forhigh performance. Manufacturers are striv-ing to avoid the issues experienced with someof the first-generation 1.6 gpf models. Since2003, most manufacturers have offered HETtoilets. In 2007, the EPA WaterSense programbegan performance qualifying HETs and other

water fixtures with the WaterSense la-bel. An HET replacement programoffers the highest water savings poten-tial. Facility owners should be aware offactors that will make the HET or ULFtoilet replacement program successful(See Figure 4-5 on p. 33).

HETs are available in the following con-figurations:

Single-flush, tank-type gravity toiletsDual-flush, tank-type gravity toiletsDual-flush, tank-type flush valvetoilets

ULF models encountered performance prob-lems, but more recent models have improveddesigns and performance.

FIGURE 4-2

Maintenance Checklist forGravity Flush and Flush Valve

(flushometer) ToiletsCheck for leaks every six months.

Encourage employees to report leaks promptly.

Adjust float valve to use as little water as possible withoutimpeding waste removal or violating the manufacturer’srecommendations.

Periodically replace valves and ballcocks.

Consider dual-flush retrofit valves for 1.6 gpf flush valvemodels.

29

Chapter 4

Tank-type pressure-assisted toiletsBattery-powered, sensor-activated dual-flush toilets

Dual-Flush ToiletsDual-flush toilets employ a dual-action flushvalve or two-button system; one for a full flush(1.6 gpf to eliminate solid waste) and the sec-ond button for a reduced flush (1.1 gpf forliquid waste). An electronic sensor-activateddual-flush unit also is available, in which thesensor activates the appropriate flush, depend-ing on the length of time the user remainsseated. Dual flush retrofit valves are availablefor existing 1.6 and 3.5 gpf units. Dual flushtechnology has been popular in Australia andEurope for the past 20 years.

Gravity Flush ToiletsGravity flush toilets are the most common ofall toilets. Gravity flush toilets most likely arefound in medium- to light-use business appli-cations.

Water efficiency options for gravity flush toi-lets include improved maintenance, retrofitand replacement options.

For a maintenance checklist, see Figure 4-2.

RetrofitRetrofit options of gravity flush systems aremost effective on units that consume morethan 3.5 gpf (pre-1980s models). For toiletsthat consume 3.5 gpf or less, some retrofit op-tions may hamper toilet performance or in-crease maintenance cost. Most retrofit optionsare available for less than $20.

Toilet Displacement Bag

Displacement devices, including bags orbottles, can reduce water flow by approxi-mately 0.75 gpf. They function by displacing

flush water stored in the tank.The devices are inexpensiveand easy to install, but do re-quire regular maintenance.Bricks or other friable objectsshould never be used as dis-placement devices becausegranular contaminants can pre-vent proper closure of the flap-per and damage flow valves.

Toilet dams are flexible insertsplaced in a toilet tank to keep0.5 to 1 gallon out of each flushcycle. Dams will last five to six

Gravity flush toilet

rim wash slot

steep sides

small water pool siphon jet

30

Chapter 4

years. A plumber should be consulted beforeinstalling such devices.

Early closure flapper valves replace the exist-ing flush valve in the tank. These devices areadjustable to optimize performance and cansave 0.5 to 2 gpf. Early closing flappers areinexpensive and usually can be installed in 10to 15 minutes, barring other problems withthe toilet’s mechanisms.

Dual-flush adapters allow users to use a stan-dard flush for solids removal or a modifiedsmaller flush for liquid and paper. Dual-flushadapters have been more popular in Europethan the United States. Dual-flush adapterscan save between 0.6 to 1.2 gpf. For this retro-fit option, facility managers should provideuser instructions about the proper use of thesedual-flush systems.

ReplacementsReplacing older commodes with HET or 1.6gpf models will provide the most water sav-ings. Most HET or 1.6-gpf replacements willoffer a payback period of less than three years.Facilities may achieve quicker payback in thesesituations:

Experience high water and/or sewercosts.

Flush Valve (Flushometer)Toilets

FIGURE 4-3

See Figure 4-3 for typical simple payback periodsfor 1.3 gpf toilet retrofits.

Have a relatively high number of usersper toilet.Currently use high water-consuming (5to 7 gpf) toilets.

Flush valve, or flushometer, toilets use waterline pressure to flush waste into the sanitarysewer system. They consist of a valve and atoilet bowl fixture. Most commercial/indus-trial facilities use flush valve toilets, especiallyin higher-use areas. (For maintenance checklist,see Figure 4-2.)

Retrofits

An economical water-saving opportunity existsto retrofit 1.6 gpf flush valve toilets with a dualflush valve. The valve is actuated upwards toflush liquid waste and downward to flush sol-ids. These valves cost as little as $40 and offera 20 percent water savings with a simple pay-back in three to four years in an office setting.

31

Chapter 4

Flush Valve(Flushometer)Toilet

For 3.5 gpf flush valve toilets, valve inserts areavailable that can reduce flush volumes by 0.5to 1 gpf. Some of these devices consist of plas-tic orifices, perforated with holes in a wheeland spoke pattern. Others actually replace theexisting valve mechanisms of a 5 gpf unit witha 3.5 gpf valve without changing the toilet bowlfixture. Do not retrofit ultra-low valves (1.6gpf) without changing a fixture bowl.

Energy Policy Act of 1992The Energy Policy Act established water efficiency plumbing standards for certain plumbingdevices. Prior to 1992, many states and municipalities concerned about water conservationwere setting unique standards, which created difficulty for manufacturers and distributorstrying to meet these numerous standards. The Energy Policy Act created a set of unifiednational standards.

Effective Jan. 1, 1994, federal standards set for maximum water usage are:

Toilets 1.6 gpfUrinals 1 gpfShowerheads 2.5 gpm @ 80 psi or 2.2 gpm @ 60 psiLavatory Faucets 2.5 gpm @ 80 psi or 2.2 gpm @ 60 psiKitchen Faucets 2.5 gpm @ 80 psi or 2.2 gpm @ 60 psi

The water efficiency standard was established to:

Preserve and protect water supply sources, both surface and groundwater.Ensure water availability for all beneficial uses.Reduce water and energy costs.Regulate and standardize plumbing fixture trade.Protect health and the environment.

The American Water Works Association estimates nationwide savings of 6.5 billion gallonsper day will be achieved by the year 2025 through these standards.

ReplacementsReplacing inefficient units with a HET or ul-tra low (1.6 gpf) flush valve mechanism andtoilet bowl will result in the maximum watersavings. It is important to note that both the

As of the date of this publication, several trade associations and local jurisdictions haveproposed further water conservation fixture standards. Revisions to these federal require-ments are expected over the next five years.

32

Chapter 4

low-flow valves and bowls should be replacedsimultaneously. A 1.6 gpf valve must be usedwith an appropriately designed 1.6 gpf bowl,or the unit will not perform adequately.

Pressurized TanksSystem ToiletsAn effective commercially-designed toilet cur-rently on the market is the pressurized tanktoilet. These units perform very well at remov-ing waste, but also are more costly. These toi-lets use water line pressure to compress air ina specially sealed tank in the toilet. Whenflushed, the compressed air greatly increasesthe flush water force. Noise was a complaintwith early models, but present models aremarkedly quieter.

Figure 4-4 shows examples of water savingsfrom implemented ULF retrofit programs inboth public and commercial settings.

Other options:Composting ToiletsWhere sewers or septic tanks are not available,composting and incinerating toilets are avail-able. Before purchasing any of these toilets,make sure building inspection programs canapprove such toilet systems.

UrinalsIt is estimated that about 80 percent ofAmerica’s 12 million urinals are old and inef-ficient. The typical water consumption forolder urinals is 2 to 3 gpf. Current federalstandards require all urinals to use no morethan 1 gpf. Urinals can have a flushometervalue or water tanks for both washdown andtrough urinals.

Pressurized Tank Toilet

Commercial/ Est. Water SavingsBusiness Sector (gpd per toilet)

Wholesale 57

Food Stores 48

Restaurants 47

Retail 37

Automotive 36

Multiple Use 29

Manufacturing 23

Health Care 21

Office 20

Hotel/Motel 16

High-Efficiency UrinalsNewer models that can significantly reducewater consumption are now available. A high-efficiency urinal is now defined as a urinal fix-ture with a flush volume of 0.5 gpf or less,including waterless units.

Some manufacturers are offering urinals thatuse as little as one pint (0.125 gallon) per flush.Flush mechanisms for these urinals includestandard manual flushometer units, hands-free hardwired sensor-operated units andhands-free battery-powered sensor-operatedunits.

Waterless UrinalsWaterless urinals can save time and moneyand conserve significant amounts of water.The waterless urinal involves a vitreous china

FIGURE 4-4

Source: The CII ULF Saving Study, 1997, California Urban WaterConservation Council. Survey of 452 California organizations.

33

Chapter 4

Making a toilet replacementproject successful

Below are factors to consider when installing new ULF or HET fixtures:

Replace highest use toilets first – highest use toilets will provide quickestpayback.Carefully choose toilet type depending on use level and the potential formisuse.Know your sewer infrastructure. Older cast iron types with a largerdiameter (4” and 6”) may have more problems transporting waste with1.6 or 1.3 gallons. Substandard wastewater pipe grading should beaddressed before installing water efficient toilets. All toilets, regardlessof flush volume, will experience problems with sewer drains compro-mised by root intrusion, sagging or broken lines, or solids build-up. Verylong commercial/industrial drain line runs can be more problematic withUFL/HET replacements if no other wastewater sources discharge nearthe toilet. Make sure the building’s water pressure is adequate if switch-ing from a gravity type to flushometer or pressurized tank toilets. Usu-ally, 25 to 35 psi or more at the toilet is required for pressure dependantsystems.ULF toilets cannot be used as trash cans. If flushing trash is a problem atthe facility, employee education with the new toilet installation is neces-sary.Ask for references from building manager, plumbers or other users whohave installed the manufactured products.Base decisions on the current models. Many design improvementscontinue to be made.Listen to noise levels of the model you are considering.A high cost does not automatically mean better performance.Ask about guarantees and returns especially for future leak problems.Choose a licensed plumber or contractor.Plan for the legal disposal of old toilets. Consult your local solid wasteauthority for recycling options or disposal requirements.

Some owners of early 1.6 ULF toilets reported dissatisfaction. Many improve-ments have been made in the 1.6 gpf toilet design to address these issues. It isimportant to remember that 1.6 gpf units are finely-tuned design systemsthat require proper use. The type of toilet should be chosen carefully for itslevel of use and application. Educating employees not to flush trash and of theimportance of water efficiency will go a long way in improving user satisfac-tion. Actual customer satisfaction surveys conducted in Santa Rosa, Calif.;Denver, Colo.; and New York City had a high customer satisfaction rate forcustomers installing ULF toilets. Less than 10 percent reported any dissatis-faction.

Use Satisfaction

FIGURE 4-5

34

Chapter 4

or stainless steel fixture and a replaceableoil-filled cartridge that traps odors.

Progressive public facilities, businessesand new high-performance LEED build-ings have been demonstrating this tech-nology in North Carolina. Waterless sys-tems are more economical to purchaseand install than flush urinals because theyhave no flushing mechanism. Waterlessurinals offer the savings of flush water andsewer charges, but these operational sav-ings are balanced with the cost of car-tridges for the drain which typically arereplaced every 7,000 uses.

Cleaning crews must have training onproper cleaning and cartridge replacementprocedures for units to function as de-signed. Waterless urinals are not withoutcontroversy, and further research isneeded to better understand long-rangeimpact and wide application of their use.Retrofit applications which were not in-stalled perfectly vertical have been prob-lematic. Pilot trials are suggested.

CASE STUDY

Urinal Timer Adjustment

The Asheville Civic Center has severallarge banks of urinals to handlerestroom traffic during large events.Sensors had been installed to continu-ously flush all urinals when therestroom doors were open. This sys-tem lead to excess water use. After awater audit by the Waste ReductionPartners program, a two-minute de-lay timer was added to the sensor sothe urinals could not flush more fre-quently than every two minutes. Thissimple change saved almost 90 per-cent of urinal water use and reducedwater consumption by 600,000 gallonsper year.

Washout andWashdown Urinals

Some models can be retrofitted to use lesswater per flush by replacing a part in theflush valve or float levels in tanks. Makesure any retrofit will continue to allowadequate removal of liquid waste. Again,bowls and flush valves need to be com-patible in design use to function properly.Installing new models that use 1.0 gpf canachieve the maximum water savings forurinals.

Special Note: Monitoring toilet usage patternsmay indicate that replacing a toilet with a lesswater intensive urinal is possible.

CASE STUDY

Install Water-Saving Fixtures

The University of North Carolina atChapel Hill installed 300 water-freeurinals in new buildings on campus, andretrofitted 30 older buildings with dualflush toilets. The installation of these300 units is expected to save the uni-versity 12 million gallons of water an-nually. In high-use areas, water-freeurinals will save at least 40,000 gallonsper unit per year. Additionally, low flowshowerheads and faucets have beeninstalled in all new resident halls foradditional water conservation savings.

Replacement options

35

Chapter 4

ShowerheadsShowerhead replacement or modification rep-resents another water efficiency area that is costeffective. Most conventional showerheads usethree to seven gpm at 60 psi water pressure.Current standards require showerheads to useno more than 2.5 gpm. These new water-effi-cient showerheads come in many different mod-els and features and typically perform very well.Water efficient showerheads also reduce energyconsumption related to hot water generation.

EPA, through its WaterSense program, is cur-rently developing specifications to establish amaximum flow rate between 1.5 and 2 gpmat a pressure of 80 psi . This flow rate repre-sents a 20- to 40-percent reduction over thecurrent 2.5 gpm rate.

Showerhead

Behavioral Modifications

Encourage users to take shorter show-ers (10 minute maximum). User aware-ness is important, especially in institu-tional settings. Shower timers are avail-able with settings for 5, 8 and 11 min-utes.Check regularly for leaks, and institutea program to require users or employ-ees to inform maintenance aboutleaks.

Plumbing ModificationsAvoid retrofitting old showerheads withflow restrictors or flow control values.Such restrictors normally produce usercomplaints. New, high-performanceshowerheads are economical, easy to in-stall and designed for water efficiency andperformance.

Replacement Options

The best water efficiency option is to pur-chase new 2.5 gpm or less showerheads.Excellent performing showerheads can bepurchased with flow rates at 1.5 gpm. The

products vary in price, from $3 to $48. Goodsingle-setting showerheads can be purchasedfor less than $10. The newer code compliantshowerheads have a narrower spray area anda greater mix of air and water than conven-tional showerheads. Wide arrays of spray pat-terns are available, including adjustable mas-sage action. Fixed and flexible position mod-els also are available.

CASE STUDY

Reduce Consumption

ASMO North Carolina in Statesvillesubstantially reduced city water con-sumption for potable/domestic use.The facility upgraded all bathroomswith waterless urinals, low flow toi-lets and motion sensor sinks. Thecompany is now saving 2.7 million gal-lons of water per year, or an estimated$16,700 in annual water and sewercost.

36

Chapter 4

Older conventional faucet flow rates can rangefrom three to five gpm. A leaking faucet drip-ping one drip per second can waste 36 gal-lons of water a day. Federal guidelines man-date that all lavatory and kitchen faucet andreplacement aerators manufactured after Jan.1, 1994, consume no more than 2.2 gpm. Fora “public” lavatory faucet, the American Soci-ety of Mechanical Engineers sets forth a stan-dard of a maximum of 0.5 gpm.

Faucet Aerator

faucet

upper washer

lower washer

aerator

ModificationAdjust flow valves to the faucet. Keepin mind this modification can also beeasily changed by users.Check regularly for leaks.Use aerators for faucet flow controllerson existing faucets. Aerators screw ontothe faucet head and add air to the waterflow while reducing water flow. They areavailable at common ratings of 0.5, 0.75,and 1.0 gpm. Flow rates as low as 0.5are adequate for hand wetting purposesin a bathroom setting. Higher flow ratekitchen aerators deliver water at 2 to 2.5gpm for more general washing purposes.Aerators cost $5 to $10 installed andtypically yield a payback within a fewmonths.Install flow restrictors. Flow restrictorscan be installed in the hot and cold wa-

ter feed lines to the faucet. Commonflow rate designs include 0.5, 0.75, 1 and1.5 gpm. Flow restrictors can be usedwhere aerators cannot be used or wherethere is faucet abuse (aerator removal isproblematic). Flow restrictors can be in-stalled for less than $25 and also yield apayback within months.

Replacements

Any new faucet purchase must have a flow rateless than 2.2 gpm. ASME specifies 0.5 gpmlavatory faucets for public restrooms. Manytypes of faucet and water control systems areavailable for commercial faucets. These in-clude:

Automatic shutoff – once the handle isreleased, valve shuts off. This style is nottypically recommended since users canwash only one hand at a time.Metered shutoff – once the lever is de-pressed, the faucet delivers a water flowfor a pre-set time period (e.g., five to 20seconds), then automatically shuts off.Federal guidelines require that meterfaucets use no more than 0.25 gallon percycle.

Infrared andUltrasonic Sensors“Electric eye” sensors are available for a num-ber of plumbing applications, including lava-tory faucets, urinals and toilets. These devicesdeliver a metered flow only when the fixtureis in use. For faucets, both the flow rate andactivation time can be adjusted. The “no-touch” activation also is helpful to prevent thespread of disease and useful for users withdisabilities. Sensored faucets, too, need to bechecked for leaks and clogged flow control-lers because of any water impurities. An infra-red sensored faucet or urinal/toilet controlscan be purchased for about $200.

Faucets

37

Chapter 4

Water Efficiency Upgrade Summary: Domestic Applications1, 2, 3

FIGURE 4-6

1Based on 2006 average N.C. water and sewer rates of $6.76 per 1,000 gallons.2Payback estimated for one shift operation. Divide payback by two and three for two- and three-shift operations, respectively.3Cost estimates are based on approximate installed cost using internal maintenance. Actual cost and payback period may vary. Options based onwidely available equipment believed not to reduce service quality or reliability. Faucet costs reflect aerator cost only, not entire fixture.4Urinal savings based on two uses per day per male employee.5Showerhead savings based on two eight-minute showers per work day and include energy savings.6Kitchen faucet saving based on three minutes of use per day.7Lavatory faucet use based on 10 seconds of use per restroom visit.

Existing TypicalStyle/Flow Water Efficiency Options/ Installed Payback

Fixture Rates Ages Water Saving Estimates Cost ($) (years) Comments

Toilets Flushometer - Post 1994 Install dual fulsh valve. Saves 20% $50-$80 3-4 User educationFlushometer- 1.6 gpf (0.3 gpf average savings). suggested. ConsiderType HET for new

applications.Flushometer - 1977 to Install new HET or 1.6 gpf $200-$300 2.0-4.5 Must change both3.5 gpf early 1990s ULF models. Saves 1.9-2.2 gpf. bowl and valve.

Consider valve inserts. Save $10-$30 0.7-1.9 Usually not rec-0.5 gpf. ommended by OEM.

Flushometer - Pre-1980s Install 3.5 gpf valve retrofit with $25-$40 0.7-1 Flushometer valves4.5 gpf no change to china bowl. Saves used in commercial

1.0 gpf. Examine dual flush valves. high use areas.Toilets Tanks-type Post 1994 Currently code compliant. $150-$300 >10 Look for EPATanks Type gravity - Consider HET for replacements WaterSense labeled

1.6 gpf or new applications. HETs.Tanks-type 1977 to Install HET or 1.6 gpf gravity/ $150-$300 1.1-3 Displacement devices/gravity - mid-1990 pressurized flush models. Saves dams not typically3.5 gpf 1.9-2.2 gpf. recommended for

3.5 gpf units.Consider early closing flapper. $20 0.5-1 Adjustable for qualitySaves 0.5-1.0 gpf. performance.

Tanks-type Pre-1980 Install HET or 1.6 gravity flush or $150-$300 0.7-2.1 Consider pressurizedgravity - devices pressurized flush models. tank systems for high5-7 gpf use areas.

Consider dams, displacement <$20 0.3-0.5 Do not use bricks.devices or early closure flapper. Loose granules inhibitSaves 0.75-2 gpf. flapper performance.

Urinals4 Flushometer - Post 1994 Consider HEU at time of $200-$450 >7 Urinals available as low1.0 gpf replacement. Saves 0.5 gpf. as 0.125 gpf.Flushometer - Install repair valves to 1.0 or 0.5 $20-$40 0.5-1.3 For non-pooling1.6 gpf gpf for non-pooling styles. styles.

Saves 0.6-1.1 gpf.Flushometer - Replace urinal fixture and retrofit $200-$450 1.8-5.63.0 gpf valves to 1.0 gpf or HEU. Saves

2.0 gpf.Showerheads5 2.5 gpm Post mid- Replace with lower flow <$35 0.6-1.3 Energy savings can be

1990s showerheads available down to two times water1.5 gpm. Saves 1.0 gpm. savings.

3-5 gpm Post 1980 Install 2.5 gpm or lower $25-$35 0.4-2showerheads.

5-8 gpm Pre-1980 Install 2.5 gpm showerheads. $25-$35 <0.2devices

Kitchen 2.2 gpm Post 1994 Code compliant - best avail- N/A N/A No less than 2.5 gpmFaucets6 able for flow and pot filling needs for kitchen applications.

3-7 gpm Pre-1980 Install aerators to reduce flow to $5-$10 0.2-2 Note energy savings.devices 2.5 gpm.

Lavatory 2.2 gpm Post 1994 Install 0.5 faucet aerators for $5-$10 0.05-0.7 Note energy savings.Faucets7 public restroom applications. Consider sensor-

controlled or metered.3-7 gpm Pre-1980 Install aerators to reduce flow to $5-$10 <0.3 0.5 gpm aerators are

devices 1.0 gpm or as little as 0.5 gpm. industry standards forpublic restrooms.

•

•

•

•

•

•

•

•

•

38

Chapter 4

Water SpigotsSelf-closing commercial valves are available forwater spigots, like those installed in publicareas. Shut-off cycles from four to 25 secondstypically are available.

Pressure Reducing ValvesFacilities should consider using a pressure-regulating valve when water line pressure ishigher than 50 to 60 psi. Lowering excessivelyhigh-line pressure helps reduce the formationof leaks and will lower water flows from spig-ots, hoses, faucets and water feed lines. A pres-sure reduction of 15 psi from 80 to 65 psi willreduce water flow by about 10 percent with-out sacrificing water service. A reduction from80 to 50 psi will correspond to about a 25percent water use reduction in light commer-cial settings.

39

Chapter 4

COOLING AND HEATING

Cooling tower

BackgroundThe use of cooling towers represents the larg-est use of water in industrial and commercialapplications. Cooling towers remove heat fromair conditioning systems and from a wide vari-ety of industrial processes that generate excessheat. While all cooling towers continually cyclewater in a closed loop, they still can consume20 to 30 percent, or more, of a facility’s totalwater use. Optimizing operation and mainte-nance of cooling tower systems can offer facil-ity managers significant savings in water con-sumption.

Cooling Tower DesignWarm water is recirculated continuously froma heat source, such as an air conditioning sys-tem or process equipment, to the coolingtower (see Figure 4-7). In most cooling towersystems, warm water (or water to be cooled) ispumped to the top of the tower where it issprayed or dripped through internal fill. Thefill creates a large surface area for a uniformthin film of water to be established through-out the tower. Fans pull or push air throughthe tower in a counterflow, crossflow or par-allel flow to the falling water in the tower.Water is evaporated carrying away the heat.

EvaporationCooling occurs in a tower by the mechanismsof evaporative cooling and the exchange ofsensible heat. The loss of heat by evaporation(approximately 1,000 British thermal units perpound of water) lowers the remaining watertemperature. The smaller amount of coolingalso occurs when the remaining water trans-fers heat (sensible heat) to the air.

The rate of evaporation is about one percentof the rate of flow of the recirculating waterpassing through the tower for every 10° F de-crease in water temperature achieved by thetower. The decrease in water temperature willvary with the ambient dew point temperature.The lower the dew point, the greater the tem-perature difference between water flowing inand out of the tower. Another rule of thumbfor estimating the rate of evaporation from acooling tower is as follows: evaporation equalsthree gallons per minute per 100 “tons” ofcooling load placed in the tower. The term“ton,” when used to describe cooling towercapacity, is equal to 12,000 Btu per hour of

For most efficient cooling, the air and watermust mix as completely as possible. Coolingis reduced when dew points are high.

40

Chapter 4

heat removed by the tower. When the dewpoint temperature is low, the tower air induc-tion fans can be slowed by using a motor speedcontrol or merely cycled on and off, savingboth energy and water evaporation losses.

FIGURE 4-7

BlowdownBlowdown is a term for water that is removedfrom the recirculating cooling water to reducecontaminant buildup in the tower water. Asevaporation occurs, water contaminants, suchas dissolved solids, build up in the water. Byremoving blowdown and adding fresh makeupwater, the dissolved solids level in the watercan be maintained to reduce mineral scalebuild-up and other contaminants in the tower,cooling condensers and process heat exchang-ers. Thermal efficiency, proper operation andlife of the cooling tower are directly related tothe quality of the recirculating water in thetower.

Water quality in the tower is dependent onmake-up water quality, water treatment andblowdown rate. Optimization of blowdown,

in conjunction with proper water treatment,represents the greatest opportunity for waterefficiency improvement. Blowdown can becontrolled manually or automatically by valvesactuated by timers or conductivity meters.

Drift LossesDrift is a loss of water from the cooling towerin the form of mist carried out of the tower byan air draft. A typical rate of drift is 0.05 to0.2 percent of the total circulation rate. Re-duction in drift through baffles or drift elimi-nators will conserve water, retain water treat-ment chemicals in the system, reduce "spot-ting" around the tower area and improve op-erating efficiency.

Make-up WaterMake-up water is water added to the coolingtowers to replace evaporation, blowdown anddrift losses. The amount of make-up wateradded directly affects the quality of water inthe systems. The relationship betweenblowdown water quality and make-up water

Cooling Tower System Schematic

41

Chapter 4

quality can be expressed as a “concentrationratio” or a “cycle of concentration.” This ra-tio is shown in Figure 4-8.

The most efficient use occurs when the con-centration ratio increases and blowdown de-creases.

Cooling Tower

Evaporation, "E"

Warm water return

Make-up water, "M"

Blowdown, "B"

Drift, "D"

Cool water to process

Water Balance : M = E + B+ D

Concentration Ratio: CR = M Quality / B Quality

Cooling Tower Water Balance

Water BalanceA simple water balance on a cooling towersystem can be determined if three of the fourfollowing parameters are known: make-up,evaporation, drift and blowdown. (See Figure4-9 for a description of the cooling tower waterbalance.)

FIGURE 4-9

CONCENTRATION RATIO

TDS of blowdowntotal dissolved solid (TDS) of make-up water

OR

μmhos of blowdownspecific conductance (μmhos) of make-up

OR

gallons of blowdown + gallons of driftgallons of make-up

FIGURE 4-8

42

Chapter 4

2 2.5 3 3.5 4 5 6 7 8 9 10

1.5 33% 44% 50% 53% 56% 58% 60% 61% 62% 63% 64%

2 -- 17% 25% 30% 33% 38% 40% 42% 43% 44% 45%

2.5 -- -- 10% 16% 20% 25% 28% 30% 31% 33% 34%

3 -- -- -- 7% 11% 17% 20% 22% 24% 25% 26%

3.5 -- -- -- -- 5% 11% 14% 17% 18% 20% 21%

4 -- -- -- -- -- 6% 10% 13% 14% 16% 17%

5 -- -- -- -- -- -- 4% 7% 9% 10% 11%

6 -- -- -- -- -- -- -- 3% 5% 6% 7%

Percent of Make-Up Water SavedNew Concentration Ratio (CRf)

Init

ial C

once

ntra

tion

Rat

io (

CR

i)

FIGURE 4-10

Blowdown OptimizationWater consumption of cooling towers can bereduced significantly by minimizing blowdownin coordination with an integrated operationand maintenance program. Blowdown is mini-mized when the concentration ratio increases. His-torical concentration ratios are 2-to-3, andgenerally can be increased up to six or morewith generic treatment options. Automationand 24-7 online monitoring can often allowcycles to be pushed to ten.

Some states have passed laws governing thequality level in a cooling tower as an attemptto promote efficient cooling tower water use.

The volume of water saved by increasing thecycles of concentration can be determined bythis equation:

V = Mi X CRi - CRf

(CRi)(CRf - I)

VMi

CRi

CRf

volume of water conservedinitial make-up water volume(before modification)concentration ratio beforeincreasing cycleconcentration ratio afterincreasing cycles

==

=

=

Water Efficiency Optionsfor Cooling Towers

43

Chapter 4

For example, increasing concentration ratiofrom two to six will save 40 percent of theinitial make-up water volume. Figure 4-10 al-lows users to easily estimate potential watersavings.

The maximum concentration ratio at whicha cooling tower can still properly operate willdepend on the make-up water quality, such aspH, TDS, alkalinity, conductivity, hardnessand microorganism levels. The use and sensi-tivity of a cooling system will also control howmuch blowdown can be reduced. Scale, cor-rosion, fouling and microbial growth are fourcritical parameters that must be controlled incooling towers. Minimum blowdown ratesmust be determined in tandem with the opti-mum water treatment program for the cool-ing tower.

Practical Guidance forWorking With a Service Contractor

Work closely with your chemical vendor or contracted service provider to reduceblowdown. Because reducing blowdown also reduces chemicalpurchasing requirements, facility personnel must keenly set upperformance-based service contracts.

Require vendors to commit to a predetermined minimum level ofwater efficiency. Have them provide an estimate of projected an-nual water and chemical consumption and costs.

Tell your vendor that water efficiency is a priority, and ask aboutalternative treatment programs that will help reduce blowdown.

When purchasing chemicals for treating cooling tower water, havethe chemical vendor explain the purpose and action of each chemi-cal. Your vendor should provide a written report of each service call. Be sure thevendor explains the meaning of each analysis performed, as well as the test results.

CASE STUDY

Cooling Tower Reduces Usage

Chem-tex laboratories in Concord in-stalled two new tanks, pumps and asmall cooling tower to cool and recyclewater that was formerly sent to the cityof Concord wastewater treatmentplant after one use. The small coolingtower and tank system cost less than$15,000 and reduced water usage byappoximately 60 percent (~20,000 gal-lons per day), and also reduced theplant’s wastewater effluent sent to thecity’s treatment plant by about 85 per-cent. Total cost savings are between$35,000 and $40,000 per year.

44

Chapter 4

Controlling BlowdownTo better control the blowdown and concen-tration ratio, facilities can install submeterson the make-up water feed line and theblowdown line. Submetering allows operatorsto carefully control water use. In some areas,evaporative water loss, as determined bysubmetering and water balances, can be sub-tracted from local sewer charges. Submeterscan be installed on most cooling towers forless than $1,000.

Recirculating water systems are blown downwhen the conductivity of the water reaches apreset level. Blowdown can be done manuallyor automatically. Automation generally allowsfor higher cycles. Typically, towers are blowndown in a “batch” process, releasing water tolower the tower volume until the make-upturns on and begins to reduce the concentra-tion in the tower. Once tower levels are re-plenished the cycle repeats. This produces asaw tooth pattern. If the mechanicals andtower load allow it to be done, proportionalor continuous make-up and blowdown sys-tems can reduce the saw tooth and increaseoverall cycles.

Recovering Sewer ChargesBecause all cooling towers lose significantquantities of water through evaporation, somewastewater utilities allow these evaporativelosses to be subtracted from utility bills. Theutilities that allow this billing adjustment typi-cally will require that a submeter be installedon the make-up water line to the coolingtower(s). Some system of reading this submetermonthly and requesting a reimbursement canbe established where allowed. Submeters canbe installed on most cooling towers for lessthan $1,000.

H2SO4

Cooling TowerWater TreatmentAlmost all well-managed cooling towers use awater treatment program. The goal of a water

treatment program is tomaintain a clean heat trans-fer surface and preservecapital while minimizingwater consumption andmeeting discharge limits.Critical water chemistry pa-rameters that require reviewand control include pH, al-kalinity, conductivity, hard-ness, microbial growth, biocide and corrosioninhibitor levels.

Depending on the quality of the make-up wa-ter, treatment programs may include corrosionand scaling inhibitors, such as organophos-phate types, along with biological fouling in-hibitors. Historically, chemicals have been fedinto the system by automatic feeders on tim-ers or actuated by conductivity meters. Auto-matic chemical feeding tends to decreasechemical dosing requirements. Current tech-nology allows chemicals to be monitored andcontrolled online 24-7 in proportion to de-mand. This ensures results and can allowcycles to be increased. Where overfeed is preva-lent, it can reduce chemical feed, too.

Sulfuric “Acid” Treatment

Sulfuric acid can be used in cooling towerwater to help control scale buildup. Whenproperly applied, sulfuric acid will lower thewater’s pH and help convert the calcium bi-carbonate scale to a more soluble calcium sul-fate form. In central North Carolina, mostplants will be able to operate six to 10 cyclesof concentration without acid feed. Along ourcoasts, acid can be used to increase cycles aswater tends to be harder and higher in alka-linity. The same can be said if hard alkalinewell water is used as tower make-up.

Important precautions need to be taken whenusing sulfuric acid treatment. Because sulfu-ric acid is an aggressive acid that will corrodemetal, it must be carefully dosed into the sys-tem and must be used in conjunction with an

45

Chapter 4

Option Advantages Disadvantages

Operation improvements to Low capital costs Nonecontrol blowdown and Low operating costschemical additions Low maintenance

requirements

Sulfuric acid treatment Low capital cost Potential safety hazardLow operating cost Potential for corrosion damage ifIncreased concentration overdosedratio, when alkalinity limited

Side stream filtration Low possibility of fouling Moderately high capital costImprove operation No effectiveness on dissolved solidsefficiency Additional maintenance

Ozonation Reduced chance for organic High capital investmentfouling Complex systemReduced liquid chemical Possible health issuerequirements

Magnet System Reduced or eliminated Novel technologychemical usage Controversial performance claims

Reuse of water within the Reduces overall facility Potential for increased fouling,facility water consumption scale or corrosion

Possible need for additional watertreatment

appropriate corrosion inhibitor. Workershandling sulfuric acid must exercise cautionto prevent contact with eyes or skin. All per-sonnel should receive training on properhandling, management and accident re-sponse for sulfuric acid used at the facility.

Side Stream Filtration

In cooling towers that use make-up waterwith high suspended solids, or in caseswhere airborne contaminants such as dustcan enter cooling tower water, side streamfiltration can be used to reduce solids build-up in the system. Typically, five to 20 per-

CASE STUDY

Reverse Osmosis Water Use

A pharmaceutical company in Claytonsubstantially reduced city water con-sumption for cooling towers by reus-ing the “reject” stream from its reverseosmosis water treatment process. Byreusing the RO “reject” water to re-place cooling tower evaporativelosses, the company is saving 10 mil-lion gallons of water per year.

Summary of Cooling Tower Water Efficiency and Treatment Options

FIGURE 4-11

46

Chapter 4

cent of the circulating flow can be filteredusing a rapid sand filter or a cartridge filtersystem.

Rapid sand filters can remove solids as smallas 15 microns in diameter while cartridges areeffective to remove solids to 10 microns or less.High efficiency filters can remove particlesdown to 0.5 microns. Neither of these filtersare effective at removing dissolved solids, butcan remove mobile mineral scale precipitantsand other solid contaminants in the water.The advantages of side stream filtration sys-tems are reduced particle loading on the tower.This ensures heat transfer efficiency and mayreduce biocide or dispersant demands.

Ozone

Ozone can be a very effective agent to treatnuisance organics in the cooling water. Ozonetreatment also is reported to control the scaleby forming mineral oxides that will precipi-tate out to the water in the form of sludge.This sludge collects on the cooling tower ba-sin, in a separation tank or other low-flow ar-eas. Ozone treatment consists of an air com-pressor, an ozone generator, a diffuser orcontactor and a control system. The initial

CASE STUDY

Eliminating Once-Through Cooling

A small medical equipment manufac-turer in Arden was using a continuoustap water flow of 12 gpm to cool a20-horsepower vacuum pump. Aftera water efficiency audit, the companyinstalled a chiller water recirculatingsystem. The company is now saving6.6 million gallons of water per year,an estimated $30,500 annual savingsin water and sewer costs.

capital costs of such systems are high but havebeen reported to provide payback in 18months.

Magnets

Some vendors offer special water-treating mag-nets that are reported to alter the surfacecharge of suspended particles in cooling towerwater. The particles help disrupt and breakloose deposits on surfaces in the cooling towersystem. The particles settle in a low-velocityarea of the cooling tower -- such as sumps --where they can be mechanically removed.Suppliers of these magnetic treatment systemsclaim that magnets will remove scale withoutconventional chemicals. Also, a similar noveltreatment technology, called an electrostaticfield generator, is also reported.

Alternative Sources of Make-Up Water

Some facilities may have an opportunity toreuse water from another process for coolingmake-up water. Clean internal wastewaterstreams such as reverse osmosis(hyperfiltration) reject water is suitable for in-process reuse. In some cases treated in-pro-cess effluent can be used as cooling towermake-up if the concentration ratio is main-tained conservatively low. Similarly, blowdownstreams may be suitable for use as in-processwater in some applications.

North Carolina’s Environmental Manage-ment Commission rules allow the use of re-claimed water, or tertiary treated municipalwastewater, for cooling tower make-up water(see p. 67). In reuse and reclaimed water ap-plications for cooling towers, water quality andsystem dynamics must be fully understood.Factors such as mechanical design, metallurgy,water chemistry and fluid flow dynamics mustbe considered.

Many facilities use “once-through” water to coolsmall heat-generating equipment. Once-through

Eliminate Once-ThroughCooling

47

Chapter 4

cooling is a very wasteful practice because water isused only one time before being sent to the sewersystem. Typical equipment that may be using once-through cooling includes: vacuum pumps, air com-pressors, condensers, hydraulic equipment, recti-fiers, degreasers, X-ray processors, welders andsometimes even air conditioners. Some areas ofthe country prohibit the use of once-through cool-ing practices. Options to eliminate once-throughcooling are typically very cost effective. They include:

Connect equipment to an existing recir-culating cooling system. Installation ofa chiller or cooling tower is usually aneconomical alternative. Sometimes ex-cess cooling capacity already exists withinthe plant that can be utilized.Consider replacing water-cooled equip-ment with air-cooled equipment. Oneexample is switching from a water-cooledto an air-cooled ice making machine. Thismust be balanced against energy costs.

CASE STUDY

Tertiary Treated Reclaim Water

A Triangle-area comfort cooling planthas been using tertiary treated reclaimwater for cooling tower make-up formore than five years. Careful moni-toring of biogrowth, corrosion ratesand system efficiency ensure long-term success.

Reuse the once-through cooling waterfor other facility water requirementssuch as cooling tower make-up, rins-ing, washing and landscaping.

CASE STUDY

Condensate Water Reuse in Towers

The Fulton County Health Center inWauseon, Ohio, is capturing HVACcondensate water and reusing this highquality water in its cooling towers. The280,000 sq. ft. hospital complex is re-using more than 353,000 gallons peryear of condensate water. The con-densate water has several positivecharacteristics for reuse that include1) being cold (around 45°F), 2) not re-quiring any treatment (i.e., very cleanwith low solids), 3) has a pH of 8.2,and 4) increases in flow as coolingtower demand increased. The waterwas able to be gravity fed to towerssystems and total project cost was lessthan $1,500.

Ideas to Reduce PotableMake-up to a Cooling Tower

Catch air handler condensation androute it to the tower, be sure to checkfor bio compatibility

Catch rinse waters from processesssuch as softeners, demineralizers, etc.and route as tower make-up

Catch rain water, filter and testappropriately to feed tower

Consider advance recycle techniquessuch as ultrafiltration

Consider other water reuse sourcesand quality, such as centrifuge blow-down

Ensure the tower is set up to mini-mize or eliminate overflow duringintermittent operation when headersmay drain to the sump

48

Chapter 4

Steps to Evaluate Streams toReduce Potable Make-up to a Tower

Analyze the sample

Model the water against the application

Balance the results vs. the investment to make it work

If the cost is large, test the results in a pilot application

CASE STUDYCondensate Used for Irrigation

The Ford Foundation uses water fromsteam condensation; condensate offcooling coils and roof drains to supplycooling towers and provide garden irri-gation. Rain runoff flows into 3,000 and13,000 gallon tanks. The 3,000 gallontank is used for watering plants and treesin the building’s atrium, using about 900gallons a week. This tank is easily replen-ished from the cooling condensate and/or rainwater within one day of use. The13,000 gallon tank is used for the cool-ing towers. Warmer summers requiringmore work of the cooling towers tomaintain the building temperature cre-ate more condensation, thus more wa-ter for the tanks. When the tanks getlow, the foundation uses water from theNew York water system. The founda-tion receives a utility credit from the cityfor this water, because it is evaporated,rather than sent into the sewer system.

CASE STUDY

Instantaneous Hot Water System

Smithfield Packing Corporation in Wil-son significantly reduced water usagewhile still experiencing an increase inproduction. The facility installed an in-stantaneous hot water system whichallows the facility to decommission itsboilers, saving approximately 11,000gallons of water per production day;equal to an 8.9 % reduction in usageand a cost avoidance of approximately$8,000 per year. The facility has alsodecreased natural gas usage by 6,269MCF, resulting in an approximate costavoidance of $85,550 per year and re-duced annual greenhouse gas emissionsby 720 tons. Total cost avoided by thisproject is approximately $93,550 peryear.

49

Chapter 4

BOILERS

Boiler

Boiler Water ImpuritiesAll boiler make-up water contains impurities.As clean steam is released from the boiler,impurities build up. The increasing concen-tration of these impurities, such as dissolvedsolids, can lead to carryover into the steam,causing damage to piping, steam traps andeven process equipment. The increasing con-centration of suspended solids impurities inthe boiler can form sludge, which impairsboiler efficiency and heat transfer capability.

BlowdownTo maintain solids at an acceptable level, wa-ter is removed from the boiler system. Thiswater bleed-off, termed “blowdown,” fromindustrial boilers is an important part ofboiler operations. Achieving the right amountof blowdown is critical. As with cooling tow-ers, insufficient blowdown can lead to exces-sive buildup of impurities. Too muchblowdown can lead to wasted water, treatmentchemicals and energy.

Blowdown is released from beneath the watersurface in the boiler’s steam drum, mud drum,bottom header or from the bottom of theboiler. Surface water blowdown is often donecontinuously to reduce the level of dissolvedsolids, and bottom blowdown is performedperiodically to remove sludge from the bot-tom of the boiler. Additionally, the blowdownheat can be used to increase the overall effi-ciency of the system.

The optimum amount of blowdown requiredis a function of boiler type, steam pressure,chemical treatment program and feedwaterquality. Because supply water quality variesfrom place to place, no hard and fast rulesexist as to the exact volume of blowdown re-quired. Blowdown rates can very from onepercent (of feedwater flow) to as much as 20percent, with the typical range of four to eightpercent.

Blowdown amount is typically calculated andcontrolled by measuring the conductivity of

50

Chapter 4

PercentBlowdown =

=

Quality ofMakeup WaterQuality ofBlowdown

x 100

TDS or (μmhos)of MakeupTDS or (μmhos)of Blowdown

x 100

Boiler water quality also is commonly ex-pressed as cycles of concentration, which issimply the inverse of percent blowdown.

Optimizing BlowdownFacility managers should know the optimumoperating parameters for their boiler waterquality. While optimizing boiler water treat-ment and control procedures can conservewater, more importantly, they will maintainproper boiler performance, extend life andsave energy. The American Boiler Manufac-turers Association and American Society ofMechanical Engineers have developed guide-lines for water purity controls in boilers. Thesecan be used as a starting point for determin-ing boiler blowdown needs. The maximumrecommended concentration limits accordingto the ABMA is listed in the table below.Operating the boiler below these levels re-

quires more blowdown, wasting water andenergy, thus increasing the cost of operation.The total dissolved solids are the sum of allnaturally occurring minerals dissolved in sup-ply water and any treatment chemicals addedto the system.

Recommended boiler blowdown practices alsoare described in Sections VI and VII of theASME Boiler and Pressure Vessel Code. Facilitymanagers can identify water- and energy-savingopportunities by comparing the blowdown andmakeup water treatment practices with theASME practices. The ASME Boiler and PressureVessel Code can be ordered through the ASMEWeb site at http://www.asme.org/bpvc/.

Maximum Recommended Concentration Limits

Boiler Operating Total Dissolved Total TotalPressure Solids Alkalinity Suspended Solids(psig) (ppm) (ppm) (ppm)

0 - 50 2,500 500 --

50 - 300 3,500 700 15

300 - 450 3,000 600 10

Automatic BlowdownControlsThere are two types of boiler blowdown:manual and automatic. Plants using manualblowdown must check samples many times aday or according to a set schedule, and adjustblowdown accordingly. With manual boilerblowdown control, operators are delayed inknowing when to conduct blowdown or forhow long. They cannot immediately respondto the changes in feedwater conditions or varia-tions in steam demand.

An automatic blowdown control constantlymonitors boiler water conductivity and adjuststhe blowdown rate accordingly to maintain the

the boiler feed and blowdown water. Conduc-tivity is a viable indicator of the overall totaldissolved solid concentration. Blowdown forboilers is usually expressed in percentage:

51

Chapter 4

desired water chemistry. A probe measures theconductivity and provides feedback to the con-troller driving a modulating blowdown valve.An automatic blowdown control can keep theblowdown rate uniformly close to the maxi-mum allowable dissolved solids level, whileminimizing blowdown and reducing energylosses.

Purchasing and installing an automaticblowdown control system can cost from$2,500 to $6,000 with generally a one- to three-year payback period on the investment. A com-plete system should consist of a low- or high-pressure conductivity probe, temperature com-pensation and signal condition equipment,and a blowdown-modulating valve.

Changing from manual blowdown control toautomatic control can reduce a boiler’s energyuse by two to five percent and reduceblowdown water losses by up to 20 percent.

Action Plan for OptimizingBoiler Blowdown

Monitor blowdown rates, feedwater qualityand blowdown water quality.Work with experienced vendors and boilerservice providers to determine best watertreatment program to complement waterefficiency goals.Establish maximum boiler water contaminantlevels.Estimate cost and operation savings in wateruse, heat loss and chemical loss that can beaccomplished by modifying concentrationratios.Evaluate implementing systems to continu-ously monitor and blowdown boiler water.

Maximizing CondensateReturnImproving condensate return is another way tominimize blowdown water and maximize cyclesof concentration at which a boiler operates. Byincreasing condensate return, operators will in-crease the concentration cycles, decrease chemi-cal usage, decrease blowdown and conserve theheat value of the high-temperature condensate.A well-functioning steam trap inspection pro-gram is essential to maximizing condensate re-turn. When steam traps exceed condensate tem-perature, the trap is leaking steam. Use infraredtemperature gun/device to check this. Steamlines and traps should be checked for leaks peri-odically and repairs should be scheduled. Suchrepairs are typically very cost effective because ofthe potential for energy savings. Condensate re-turn systems and automatic shut-off controlsshould be considered for boiler systems not uti-lizing them. Consultation can be conducted withboiler vendors, service providers and other tech-nical assistance providers.

Improving External andInternal Water TreatmentExternal or feedwater pre-treatment systemsremove impurities form the boiler feedwater.Treatment systems address three areas:

Removal of suspended solidsRemoval of hardness and other solubleimpuritiesOxygen removal

1.2.

3.

There are several technologies available to pre-treat boiler feed water. These include soften-ers, reverse osmosis and demineralization. In-creasing feedwater quality will increase thecycles of concentration at which a boiler canoperate.

Internal water treatment regimes for boilersseek to manage corrosion and deposits.Choices for internal and external water treat-

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ment approaches are interdependent. Whileseeking to optimize boiler water systems, theimportance of using knowledgeable people toensure proper evaluation of water treatmentneeds cannot be overemphasized. It is best toutilize someone familiar with boiler system op-eration as well.

Blowdown Heat RecoveryUnitsThe evaluation of reclaiming heat fromblowdown is a wise consideration. Systemswith continuous blowdown rates exceedingfive percent of the steam generation rate areoften good candidates for a blowdown wasteheat recovery system. The blowdown water hasthe same temperature and pressure as theboiler water. Before this high-energy waste isdischarged, the residual heat in blowdown canbe recovered with a flash tank, a heat ex-changer or the combination of the two. Aboiler blowdown heat recovery project at Au-gusta Newsprint Mill in Georgia saved thecompany $31,000 in fuel costs and 14,000MMBtu in energy annually.

CASE STUDY

Clean Cooling Water Reuse

Safelite Glass Company in Enfield, N.C.,utilizes water from air compressors andhydraulic fluid cooling water for boilermakeup. Clean once-through coolingwater is a good candidate for boilerwater make up. The reuse practicesaved 8.5 million gallons of city waterper year and was implemented for$3,000. Simple payback was twomonths.

CASE STUDYChemical Free Boiler Water Treatment

Vanir Solar Construction in Fletcher op-erates a 150-hp boiler around the clockduring the heating season. The boiler hasa high condensate return and very high-quality make-up water. The water treat-ment system for the boiler utilized aconventional approach of chemical treat-ment using phosphate, hydroxide alka-linity (caustic) and sulfite. Beginning inthe 2007-08 heating season, a non-chemical treatment water system wasinstalled by Fluidyne International. Thenew treatment system reduced boilercorrosion and deposits while significantlyreducing boiler blowdown water. Withvisual inspection, rusty deposits in theboiler and condensate return lines weredisappearing from the walls of the wet-ted areas. The annual (heating season)savings related just to blowdown, includ-ing water, sewer and energy costs, was$4,070. The new system is saving189,000 gallons of water annually. Sig-nificant additional savings were achievedin eliminated chemical costs and chemi-cal servicing.

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KITCHEN & FOOD PREPARATION

Although commonly overlooked, there aremany ways to reduce water usage in thekitchen. Traditionally, saving water has notbeen a major consideration of commercialfood preparers. Many establishments cite thelack of money or employees as reasons for notusing water conservation methods. Case his-tories have shown that water efficiency pro-grams are cost-effective, and most initial costsare retrieved within a two-year period. Partici-pation in municipal water efficiency programsshows that the food preparation sector is in-terested in striving for high efficiencies in itswater use.

Inefficient uses of water in kitchen operationscome mainly from two areas: equipment de-sign and behavioral patterns. The main typesof water-using equipment found in kitchens

CASE STUDYGeothermal Energy Use

The Proximity Hotel, located inGreensboro, has an innovative refrig-erator system in its kitchen that usesgeothermal energy instead of the con-ventional water-cooled systems, pro-viding significant water savings.

are dishwashers, faucets, ice-making machinesand garbage disposals. Improved technologyhas eliminated many of the water issues asso-ciated with equipment, as more rigid standardshave been created to curtail excessive water

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Commercial Kitchen/Cafeteria OperationsWater UseExisting High Savings

Equipment Type Traditional Standard Efficiency Potential Comments

Commercial Undercounter 1-1.8 gal/rack No standard 1 gal/rack Up to 0.8 Machines with an overall heightDishwashers gal/rack of less than 36”; rack of dishes

remains stationary within machineduring sequential wash and rinsesprays. High temp machines aremost water efficient.

Stationary 1.1-2.2 gal/rack No standard 0.95 gal/rack Up to 1.2 Includes machines commonlySingle Tank Door gal/rack referred to as pot, pan and utensil

washer. Also applies to machinesin which the rack revolves on anaxis during the wash and rinse

\ cycles. High temp machines aremost water efficient.

Single Tank 0.7-1.4 gal/rack No standard 0.7 gal/rack Up to.7 A single tank conveyor machineConveyor gal/rack has a tank for wash water

followed by a final sanitizing rinseand does not have a pumpedrinse tank.

Multi Tank 0.54-1.2 gal/rack No standard 0.54 gal/rack Up to 0.58 Machines with one or more tanksConveyor gal/rack for wash water and one or more

tanks for pumped rinse water.Followed by a final sanitizing rinse.

Pre-rinse Handheld hose- 2-5 gpm 1.6 gpm at 60 psi 0.4-3.4Spray Valves mounted dish gpm

sprayersCommercial Compartment 25-35 gal/hr No standard ENERGY STAR Up to 33Steam Steamers Qualified gal/hrCookers cookers

average2 gal/hr

use. Water audits of commercial facilities haveshown that 60 percent of identified water sav-ings comes from simply installing 2.2 gpm fau-cet aerators in all kitchen sink outlets. An ef-fective part of water savings in kitchens is at-tributed to behavioral patterns in facilities.Awareness programs, education, training andjob performance measures can influenceproper behavioral patterns of staff.

Dishwashers*Commercial dishwashers, considered to beone of the largest water and energy consum-ers in a food service area, often use more thantwo-thirds of the overall kitchen water use.There are four main classes of commercialdishwashers: undercounter, stationary rack

door type, rack conveyor and flight type. Eachclass of dishwasher may employ single or mul-tiple wash tanks, and use hot water (high-tempmachines) or chemicals (low-temp machines)to achieve final rinse dish sanitization. Re-quirements for machine class and size can becalculated by estimating the amount of trafficthat will be served in the food service area.

Water usage across commercial dishwasherclasses does not appear to be directly relatedto the size of the machine and varies from .33gallons per rack to 20+ gpr. A typical com-mercial dishwasher uses approximately fourgpr. Using an appropriately sized, water effi-cient model will save a significant amount ofwater.

FIGURE 4-12

*Taken from the Alliance for Water Efficiency - Commercial Dishwashing Web site.

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Undercounter

The smallest of commercial dishwashers,undercounter dishwashers, are best suitedfor small establishments of about 60 people.They commonly are used in nursing homes,churches, small food service areas and of-fice buildings. The undercounter machinesare similar to residential dishwashers in thatthe door opens downward with rack(s) roll-ing out onto the lowered door for access.

A revolving wash arm handles the wash andrinse cycles, with a small holding tank be-ing automatically drained after each cycle.An automatic timer controls cycle length.Undercounter machines come in both hotwater and chemical sanitizing models, withoptional booster heaters for the latter. Hotwater machines are the most water efficient.

Stationary Rack Door

Designed to service 50-200 people, stationaryrack door machines are the most widely usedfor commercial dishwashing machines. Doormachines are used in schools, hospitals,churches, restaurants, catering businesses, fast-food establishments and as glass and utensilunits in larger operations.

These box-shaped machines have one or mul-tiple doors that slide vertically for loading andunloading. Stationary rack door type machinesare available in both hot water and chemicalsanitizing models. Hot water machines are themost water efficient. These “dump and rinse”machines have a single tank for water anddetergent, which are circulated in measuredvolumes and temperatures. Two revolvingspray arms distribute wash solutions evenlyover the dishes. Some stationary rack doormachines have the ability to recycle rinse wa-ter to be used again in a wash cycle.

Types ofDishwashing Machines

Undercounter

Stationary rack door

Rack Conveyor

Flight

Rack Conveyor

Rack conveyor, or c-line, machines use a mo-tor-driven conveyor belt to move the rack-loaded dishes through a large tank with sepa-

rate wash and rinse compartments. Mostwidely-used in hotels, large restaurants, hos-pitals, schools and universities, these machinesare well suited for service of 200 or morepeople, accommodating most heavy food ser-vice operations.

Rack conveyors come in varying sizes, withavailable additions such as pre-wash units, side-loading trays, condensers and blower-dryers.A single tank holds the water and detergentat a regulated temperature. The wash solutionis pumped through multiple spray arms (re-volving or stationary) that run constantly oncethe machine is operational, regardless of thepresence of a dish rack. The rack is then sentthrough the rinse compartment, where it issprayed with 180ºF water by spray nozzlesabove and below the rack. Rack conveyormachines with multiple tanks differ in thatsome use stationary vs. rotating spray arms.The racks are then sent into a pump-drivenrinse tank that rinses the dishes heavily. Thisprocess usually uses recycled water from thefinal rinse. All rack conveyor machines have atimer control for the speed of the conveyor toassure proper wash and rinse times.

Water efficient measures, such as the installa-tion of an electric eye sensor (that keeps theconveyor from running when there are no

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dishes on the racks) make conveyors morewater-, energy- and cost-effective. CASE STUDY

Adopting Water Efficiency Practices

The Angus Barn restaurant in Raleighreduced daily water usage by more than10,000 gallons by installing new waterefficient equipment and adopting waterefficiency practices. New dishwashers,with a significantly shorter wash cyclethat still meets performance and sanita-tion standards, were installed. An olderwater-cooled ice machine was replacedwith an air-cooled ice machine. A vari-ety of low-flow restroom fixtures includ-ing faucets, automatic flush urinals andtoilets that meet performance expecta-tions were installed. Changing fromhosing kitchen floors every night tomopping floors on alternate nights andhosing the floor in between decreasedwater usage. Sanitation was not com-promised with any of these water-effi-cient techniques.

Flight

Similar in that they use a conveyor belt to movedishware, flight-type machines do not haveracks. Rather, dishes are loaded directly ontothe belt. Flight-type dishwashers provide highvolume washing capability needed only in thelargest institutional, commercial and indus-trial facilities. Variations in possible machineadditions include power scrapers, power wash,power rinse, final rinse and blower-dryer.

Water efficient strategies for these machinesinclude the recirculation of final rinse water,electric eye sensors, extra-wide conveyors andlow-energy built-in booster heaters. These ad-ditions can translate to water savings as muchas 47 percent, while maintaining loads of morethan 14,000 dishes per hour.

Water Efficient Practicesfor DishwashersThe volume of consumption in dishwasherscan be reduced by a variety of practices, all ofwhich target awareness of equipment andoperational needs.

Behavioral Modifications

Educate staff about the benefits of wa-ter efficiency and the importance ofhand scraping before loading a dish-washer.Instruct staff to quickly report leaks andtroubleshoot.Run rack machines only if they are full.Try to fill each rack to maximum capac-ity.

Mechanical Modifications

Reuse rinse water to pre-rinse or washdishes.Keep flow rates as close as possible tomanufacturer’s specifications.Install advanced rinse nozzles.

Install “electric eye sensors” to allowwater flow only when dishes are present.Install door switches for convenient on/off access.Check voltage of booster heater to makesure it fits the machine.Use “steam doors” to prevent loss ofwater due to evaporation.Check volumes of service and estimatefacility needs. A better option may be alarger machine that has a lower waterflow per rack rate.

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Kitchen Faucets andPre-rinse SprayersFaucets can waste large amounts of water, asthey are the most heavily used water source inkitchens. Conventional faucets, with typicalflow rates of 2.5 to 4.0 gpm, can waste as muchas 40 gallons of water a day when not fullyclosed. Since 1994, water efficiency standardshave been federally mandated, requiring thatall post-1994 manufactured faucets consumea maximum of 2.5 gpm @ 80 psi. But manyfacilities have older fixtures with rubber gas-kets that wear and deform because of highamounts of hot water use. By simply install-ing a brass gasket and an automatic shut-offnozzle, a facility could save as much as 21,000gallons of water per year. There have beenmany adjustments and technology advance-ments in faucet design as a variety of low-flowfaucet types are being manufactured. Foot-ac-tivated kitchen faucets will reduce water usewhile providing additional convenience. Fau-cets used in kitchens will be primarily the con-ventional type or pre-rinse pressure sprayers.

Quick Tip

Pre-rinsing dishes by hand beforeloading the dishwasher can useup to 20 gallons of water. Simplyscrape food off dishes and load.ENERGY STAR qualified dish-washers and today's detergentsare designed to do the cleaningso pre-rinsing can be eliminated.If dirty dishes are going to sitovernight, use the dishwasher'srinse feature that uses a fractionof the water and time used tohand rinse.

There are a variety of modifications that canbe employed for all types.

Water Efficiency Optionsfor Kitchen Faucets

Adjust flow valve to reduce water flow.Check for leaks and worn gaskets.Install a flow restrictor to limit maxi-mum flow rate to 2.5 gpm or less.Install a 2.5 gpm faucet aerator, maxi-mizing flow efficiency by increasing air-flow to the stream.Consider infrared or ultrasonic sensorsthat activate water flow only in the pres-ence of hands or some other object.Install pedal operated faucet controllersto ensure valves are closed when not inuse.Educate staff to look for leaks and bro-ken faucets in their area.Do not leave faucets on to thaw veg-etables and other frozen foods.Post water conservation literature andreminders to staff around work areas.

Pre-Rinse SprayersKnown as high-efficiency sprayers, these inex-pensive nozzles use less water and can save acommercial kitchen hundreds of dollars a yearin energy costs alone. The sprayers can alsocut the water bill.

Pre-rinse sprayers are an essential componentof kitchen operations. They are used to removeleftover grease and food off dishes, pots andpans before they go into a dishwasher. Whileconventional sprayers use between 2.5 and 4gallons of water per minute, the high-efficiencysprayers use from 1.6 to 2.65 gpm.

The new generation of sprayers also comeswith an automatic shut-off valve at the hosehead, so water is supplied only when needed.

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Ice MachinesIce machines have many commercial uses,from restaurants to lodges, and can use sig-nificant amounts of water, depending on thetype of machine and the desired type of ice.

Ice machines are composed of the followingcomponents: a condensing unit used for cool-ing, an evaporator surface for ice formation,an ice harvester, an ice storage container, and,in some models, a dispenser. The type of con-denser an ice machine uses will have the larg-est effect on water use. Two types of condens-ers are available: air-cooled and water-cooled.

CASE STUDYFoot-actuated Faucet

By installing a foot-actuated faucet, onefood service facility reduced itsmonthly water usage by 3,700 gallons.This translated to annual savings ofnearly $700.

Garbage DisposalsStudies show that garbage disposals can wastea significant amount of water. It is recom-mended that their use be minimized or elimi-nated from kitchen operations. Many facili-ties use strainers or traps that employ a meshscreen to collect food waste for proper wastetreatment. Another option is to install strain-ers in sinks, leaving the food matter in thesink for disposal in trash receptacles orcomposting units.

Water-cooled machines use 10 times as muchwater as air-cooled machines and water rarelyis recirculated. In comparing water- and air-cooled compressors, the compressor horse-power at design conditions is invariably higherwith air-cooled machines. However, operatingcosts frequently compare favorably during afull year.

The desired quality and visual clarity of icealso will influence water consumption. Icequality, machine cleaning and water efficiencyall need to be balanced for optimum opera-tion.

Ice Machine Water UseWater Use

Building Existing High SavingsEquipment Type Type Traditional Standard Efficiency Potential Comments

Commercial Ice-making head Operations Water cooled None Air cooled 125 gal/100 Typically larger volumeand remote requiring large units can use units can use lbs. of ice applications where ice-condensing units volumes of ice 150 gal/100 lbs. 25 gal/100 making head and storage

of ice lbs. of ice bin are separate or ice-making head and condenserunits are separated

Self-contained Most common Water cooled None Air cooled 120 gal/100 Free-standing units whereconfiguration units can use units can use lbs. of ice ice-making unit and storagefor low volume 150 gal/100 lbs. 30 gal/100 compartment are housedapplications of ice lbs. of ice together in a single cabinet

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COMMERCIAL LAUNDRIES

Commercial, industrial and institutional fa-cilities include those that wash linens, uni-forms and other items for hotels and motels,hospitals, nursing homes, prisons, universitiesand restaurants. Large amounts of water areregularly used in laundering facilities for op-erations that include the wash and rinse cyclesof washing machines, steam-heated dryers,steam-pressing equipment and reclamation ofdry solvent.

Traditional washer-extractor machines used bymost laundry facilities operate with a rotatingdrum that agitates the laundry during wash

and rinse cycles, then spins it at high speedsto extract water. Washer-extractors and mostother traditional large-scale washing machinesuse fresh water for each wash and rinse cycle.The capacity for washer-extractors ranges from25 to 400 dry pounds per load and use 2.5 to3.5 gallons of water per pound of laundry.Water efficient laundering equipment, suchas continuous-batch washers and water recla-mation systems, can reduce water use by asmuch as 70 percent at commercial, industrialand institutional facilities equipped with tra-ditional washer-extractors.

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Water Efficiency MeasuresWater and wastewater costs represent morethan 50 percent of the total operating costs ina typical commercial, industrial and institu-tional laundry operation. In general, two gal-lons of water used per pound of clothes isconsidered a “good” water efficiency standardfor commercial, industrial and institutionallaundries; though this is not always achievablefor heavily soiled fabrics. Water efficiencymeasures should not impair the cleaning orsanitation goals of the laundry operation.Water efficiency measures that may be appli-cable to commercial, industrial and institu-tional laundry operations include:

Operate laundry equipment with fullloads only.Reduce water levels, if possible, for par-tial loads.Replace or modify existing conventionallaundry equipment to reduce water use.Replace traditional commercialclothes washers (vertical axis) withhigh efficiency washers (horizontalaxis), which can save as much as two-thirds of the energy and water usedby traditional models.Install a computer-controlled rinse wa-ter reclamation system. These systemscan save as much as 25 percent ofwash load’s water demand by divert-ing rinse water to a storage tank forlater reuse as wash water.Install a wash and rinse water treat-ment and reclamation system, exceptin very rare situations where healthcodes prohibit such use in specializedsituations. By recycling both wash andrinse water, these systems can reducea laundry’s water demand by about50 percent.Install a continuous-batch (or tunnel)washer, which can reduce water demandby about 60 percent compared with thatof washer-extractors.

Install an electrically generated ozonelaundry system, which can reduce wateruse by about 10 percent compared withthat of traditional laundering systems.The ozone acts as a cleaning agent andalso reduces detergent use by 30 to 90percent.Consult service personnel and thelaundry’s supplier of chemicals for thewasher-extractors to ensure that equip-ment is operating at optimal efficiency.Avoid excessive backflushing of filtersor softeners; backflush only when nec-essary.Place “save water” notices in hotel andmotel guest rooms, urging guests to savewater by minimizing the amount oflinen that needs to be laundered.

The Commercial Laundries section was taken from the“Handbook of Water Use and Conservation,” by AmyVickers.

CASE STUDY

Rinse Water Reuse

A laundry facility in Manchester, N.H.,saves approximately 675,000 gallonsof water per month by using a hori-zontal flow “tunnel-type” washingmachine that reuses rinse water forbleaching and washing. This washingsystem is capable of using approxi-mately 40 percent less water than aconventional type machine, based onequivalent cleaning requirements.

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CLEANING AND RINSING APPLICATIONS

Most industrial and commercial businesseshave a variety of cleaning and rinsing applica-tions that can consume large volumes of wa-ter. Water efficiency techniques presentedhere address general water uses for processchange-overs, equipment clean-out, parts rins-ing, tank rinsing, line flushing, floor clean-ing and other applications. Because this sec-tion is generic in nature, the water efficiencyconcepts presented will need to be individu-alized for specific business needs and any regu-latory cleanliness standards. (Also see sectionson metal finishing, textiles and food processing inChapter 5 for more specific water efficiency appli-cations.)

Education: First andForemostEmployees must be aware of the need for wa-ter efficiency. Many cleaning processes can bemade significantly more efficient by simple

measures. If employees are actively solicitedand involved in water reduction efforts, be-havior and equipment modifications will suc-cessfully reduce water consumption.

Dry Clean-upDry clean-up means using brooms, brushes,vacuums, squeegees, scrapers and other uten-sils to clean material before water is used. Bycollecting the majority of wastes, residues orcontaminants in a dry form, large volumes ofwater and wastewater can be eliminated. Thebulk of solid materials can be more efficientlyremoved in dry form before water is intro-duced for secondary washing.

Examples of Dry Clean-up PracticesSweeping floors instead of hosing withwater.Vacuuming or sweeping dry material spillssuch as salt or dyes instead of using water.

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Use squeegees and scrapers first to re-move residuals from machines, such asink sludge from machine troughs be-tween color change-overs.Vacuuming or sweeping particulateemissions (dust) instead of hosing withwater.Use rubber squeegees to collect food pro-cessing residuals from the floor beforehosing with water.Use “pigs” to purge residuals from pipesbefore flushing with water.

CASE STUDY

Dry Clean-up

The Equity Group in Reidsville insti-tuted a comprehensive program toreduce water use and wastewaterpollutant loading in its food process-ing operation. Employees were trainedto remove all dry waste from floorsand equipment for cleaning. Becauseof dry clean-up practices, much of thewaste food residuals can have a sec-ondary use, such as for animal food.Dry clean-up, improved employeeawareness and other operationalmodifications saved 1.25 million gal-lons per month and reduced organicpollutant loading to wastewater by 50percent.

Benefits of Dry Clean-upSaves water and reduces wastewater.Reduces water, wastewater and sur-charge costs.Reduces pollutant loading enteringwastewater system.Saves energy for processes that use hotwater.Reduces hydraulic capacity demands onany wastewater treatment systems.

Better enables the recovery of processmaterial. Also enables the recycling orcomposting of “dry” collected materials.

Eliminate/Reduce FloorWashing Where Feasible

Many floor surfaces (i.e., warehouses, of-fices, automotive garages, non-critical pro-cessing areas, facility support operations,etc.) do not need to be washed with water.If necessary, use dry absorbents and sweepor vacuum these areas.Find and eliminate the source of spills and

CASE STUDY

Dry Clean-up

Tyson Foods in Sanford reduced waste-water discharge volumes and limitedthe amount of production material lostto the sewer; totaling approximately$29,000 annually in water and sewercost avoidance. Employees frequentlyused water hoses to wash the materialdown the drain. To reduce water us-age, Tyson shut off and locked all wa-ter-cooled compressors during the firstand second shifts and educated employ-ees on the need to reduce water us-age. Tyson also modified productionequipment to reduce material losses tothe floor and covered production linesnot in use to reduce unnecessary clean-ing. As a result of implementing thesemeasures, Tyson reduced its averagedaily discharge from 35,000 to 15,000gallons and substantially reduced theamount of production material lost tothe sewer. Sanitation was not compro-mised with any of these water-efficienttechniques.

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CASE STUDY

High-Pressure Washers

A food processing facility in St. Paul,Minn., replaced garden hoses withhigh-pressure washers to clean equip-ment that processes flour products.The new high-pressure washers cost$200 each. Equipment now is cleanedquicker and more efficiently using halfthe water. The washers save 217,000gallons of water per year, and the pay-back was less than three months. Sani-tation was not compromised with thisapplication.

Use Efficient SprayWashing/RinseMany improvements can be made to the wa-ter delivery system for washing and rinsing.Proper selection, control, use and mainte-nance are essential. Consider these sugges-tions:

Do not use a hose as a broom. This prac-tice is a waste of valuable labor, water andenergy.Use efficient spray nozzles with automaticshutoffs on the end of hoses. Garden hosenozzles are not very efficient.Consider high-pressure washers to cleanmore quickly and efficiently.Consider pressurized air-assisted spraynozzles to provide more cleaning force withless water.Use low-flow “fogging” nozzles to rinseparts efficiently.Use flow restrictors in water lines that sup-ply hoses and pressure washers.Use timers to shut off process water rinseswhen process is shut down.Turn off running water when not in use.Ensure stationary spray nozzles are aimedproperly.Review nozzle spray patterns for optimumapplication. Fan, cone, hollow cone, airatomizing, fine spray and fogging are a fewexamples of nozzle spray patterns.Replace worn spray nozzle heads. They canresult in poor spray patterns and excessivewater consumption.Use countercurrent washing techniques.(See Chapter 5.)Use conductivity controllers to regulaterinse water flow rates. (See Chapter 5.)

leaks that may be the sole reason why wa-ter washdowns are needed.Spot mop if necessary.Use floor mats, “clean-zones” and othermeans to reduce the tracking of waste anddirt residuals throughout a facility.

Use spray washing/rinsing techniques fortank cleaning vs. refilling/dropping tankwashwater.

Other Improvements tothe Cleaning Process

Tanks, vats, pipeline and other equipmentsurfaces can be coated with a TeflonTM non-stick surface. This allows for easier cleaningduring process line changeovers and clean-up.

TeflonTM Surface Coatings

Changes in the type, temperature and concen-tration of cleaning solutions can save water.

Cleaning Chemical Changes

Operational Controls and Maintenance

Overflow controls should be in place for fill-ing tanks and vessels.

Sub-Metering Water UseSome businesses restrict water flow to an en-tire processing area and force water operatorsto find the optimum ratio level for individual

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CASE STUDY

Cleaning Solution Reuse

Campbell Soup Company in Maxtoninstituted a corporate wide integratedpollution prevention program. For wa-ter efficiency measures, Campbell soupused dry-clean-up procedures for floorsand equipment, installed process wa-ter flow meters, and eliminated watertransport (fluming) of scrap. A continu-ous maintenance/housekeeping sched-ule was implemented instead of theprevious once-a-day practice. Thesewater efficiency techniques have saved$125,000 annually in operating costs.The program also improved solids col-lection and recycling.

Vehicle WashwaterRecyclingMany commercial water recycle systems areavailable for fleet maintenance and vehiclecleaning. With a recycle water permit fromthe proper authority, facilities can install awashwater recycle system for vehicle cleaning.

Washwater recycling systems provide severaladvantages over typical wastewater disposal:

These systems allow for simple cleanupof contaminants from spills or systemfailures by preventing entry to the sani-tary sewer or septic system.

1.

Typical washwater recycling systems consist ofa sedimentation basin for grit/sand removal,an oil/water separator, filtration and a disin-fection unit to prevent biological growth. Ba-sin/sump compartments are used to settle grit,sand and other solids, and also used to skimany floating oils. Water then is filtered, typi-cally using a multimedia filter that removessolids in the water larger than five to 20 mi-crons in diameter. The filtered water is oxi-dized/sanitized to reduce organics and meetany health/safety standards for non-potable

activities. Sub-metering and monitoring allowsexcessive water consumption and leaks to bequickly detected and corrected.

These systems reduce costs for wateruse and disposal.Many of the systems are pre-engi-neered, have a proven track record,and can be submitted for permit issu-ance from previously approved plansand specifications.

2.

3.

CASE STUDY

Cleaning Solution Reuse

T.S. Designs, a screen printer in Burlingtoncleaned printing screens using strong oxi-dizing solution in manual wiping applica-tion. To reduce chemical consumptionand save water, T.S. Designs installed a43-gallon reclamation tank to continu-ously filter and circulate the aqueouscleaning solution past the printing screensuspended in a tank. A similar reuse sys-tem was used for a stain and haze remov-ing wash step. The reuse process allowscleaning solution to be used continuouslyfor one month. With the reuse system,less concentrated and safer solutionscould be employed. The reuse systemsaves $5,200 per year in chemical, waterand sewer costs.

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water reuse. Water then is stored and pumpedback to the washing bay for reuse.

Although such systems can be nearly closed-loop, except for occasional solids removal andfilter backwash wastewater, occasionally watermust be changed due to buildup of dissolvedsolids (salts). Washing practices and dischargesto the recycling system must be closely con-trolled, as they will not handle shock loads.Maintenance to the treatment/recycle equip-ment also is very important. Pre-engineeredunits for single wash bays cost approximately$20,000. The regional staff for the N.C. Divi-sion of Water Quality can provide additionaldetails about permits for a recycling system.

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REUSE AND RECLAMATION

Maximizing utility of in-process water is ac-complished by using it more than one time todo work. Water quality characteristics willdetermine if multi-functional use of in-processwater is acceptable for achieving necessaryproduct quality control/assurance. Fortu-nately, many water treatment technologies canprovide cost-effective opportunities to reducewater supply demand and the resultant sav-ings can be used to justify capital costs. De-pending on water quality requirements for thestage of use, water may simply be recirculatedor require only basic treatment such as solidsettling, oil skimming and/or filtration usingcartridge, bag, disk, indexing fabric or sandfiltration. (See Figure 4-13.)

Water quality standards need to be carefullyestablished for each point of multiple-use. Forhigh water quality demands, technologicallyadvanced water treatment techniques existsuch as ultrafiltration, nanofiltration,hyperfiltration (reverse osmosis), carbon filtra-tion and ion exchange.

Additional uses of in-process water effluentscan also allow the user to salvage a valuableproduct that presently is being discharged asa wastewater constituent, such as cleaningchemicals in washing solutions or valuablemetals in rinsing solutions. This may also re-duce wastewater treatment surcharges.

Making Water Do MoreWork

In-Process Water ReuseRulesAreas in North Carolina are approaching lim-its on seasonal availability of high-quality rawsource water. One way to reduce withdrawalof source water is to reduce demand by imple-menting reuse of industrial in-process waste-water to increase water efficiency. NorthCarolina’s Environmental Management Com-mission rules support the reuse of industrialin-process wastewater to increase water effi-ciency.

Title 15A NCAC Subchapter 2T, Section.1000 applies to closed-loop recycle systemswhere non-domestic wastewater is repeatedlyrecycled back through the process in whichthe water was generated. This section permitsby regulation (i.e., no permit needed) the re-turn of wastewater contained and under roofwithin an industrial or commercial process.Spill control plans are required for these sys-tems that do not have secondary containment.An operations and maintenance plan shall bemaintained for all closed-loop systems. A re-siduals management plan shall be maintainedfor all systems that generate residuals.

Consider staged cleaning techniques wherethe first- and second-pass cleaning water issaved for further use or reclamation of chemi-cals.

CAUTION: RECLAIMED WATER DO NOT DRINK

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Industrial in-process water reused withinthe facility that originated the effluent.Cooling tower make-up water.Fire-fighting or extinguishing water.

Reuse of industrial in-process effluents areallowed as specified in the Subchapter 2Trules. Before constructing a water reuse sys-tem, it is important to verify if a permit willbe needed. Modifications to an existing waterreuse system may require permitting and/ormodification to an existing permit (e.g., pre-treatment industrial user permit).

All types of industrial/commercial water re-use require the facility to assure protection ofemployee health and safety, and to notify em-ployees that non-potable water is being reused.All valves, piping and storage facilities of in-process reuse water must be tagged or labeledto inform employees that the water is not in-tended for drinking.

Reclaimed WaterSystems RulesReclaimed water must meet two criteria. First,whether treated or untreated, it must meetspecific qualitative standards. Second, it mustalso be reused in a beneficial manner for thepurpose of conservation of the state’s waterresources. The most common reclaimed wa-ter is effluent from a tertiary wastewater treat-ment process. Reclaimed water utilizationserves to offset the use of potable water, sur-face water and/or groundwater. The water

N.C. Division of Water Quality issued non-discharge permitting is required for closed–loop recycle systems that are not under roof(i.e., exposed to precipitation inputs) and/orutilizing an earthen basin for storage. Specialconditions apply as defined in the Subchap-ter 2T rules.

Industrial in-process effluents can be directlyreused without a DWQ non-discharge permitin these specific situations:

resources benefit derived from the use of re-claimed water is to offset withdrawal of rawwater for supply from another location in thehydrological system.

The rules in Title 15A NCAC Subchapter 2T,Section .0900 apply to reclaimed water sys-tems. Reclaimed water effluent standards arevery stringent in order to provide for protec-tion from pathogens. Reclaimed water systemsare classified in the rules as conjunctive onlyif the wastewater treatment plant that pro-duces the effluent has the capability to dis-pose of this water by another method (e.g.,NPDES permit). Facilities producing re-claimed water are permitted by the N.C. Divi-sion of Water Quality Aquifer Protection Sec-tion, Land Application Unit.

CASE STUDY

In-Plant Water Reuse

Previously, the open-loop cooling sys-tem on the emergency generator at theMichelin Aircraft Tire Corporation inNorwood pumped 150 gallons of wa-ter per minute into the storm wateroutflow drains. The facility replaced theopen-loop generator cooling systemwith a closed-loop generator coolingsystem that recycles water from anonsite cooling pond. The facility also re-placed bathroom faucets and toiletswith more efficient reduced flow, mo-tion sensor models. As a result of theclosed-loop cooling system and bath-room fixture replacements, the facilityreduced water consumption by 4.8million gallons per year.

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In some localities, it is now possible for cus-tomers to receive reclaimed water that is dis-tributed directly from a publicly owned waste-water treatment plant. Reclaimed water dis-tribution piping is distinguishable from po-table lines by being colored purple or wrappedand continuously embossed or integrallystamped or marked "CAUTION: RE-CLAIMED WATER - DO NOT DRINK." Nocross-connections are allowed to occur be-tween the reclaimed water system and potablewater systems. Where potable water is usedto supplement the equipment using reclaimedwater, an air gap must separate the potableand reclaimed water. The supplemental sys-tem is then subject to approval by the potablewater supplier.

Once reclaimed water is distributed to custom-ers it is not allowed to be directly discharged

FIGURE 4-13

Golf course and landscape irrigationDust control

to the surface waters of the state by the cus-tomer. If the reclaimed water is used to sup-ply a landscape irrigation system, runoff intostormwater catchments and conveyances is notallowed.

After reclaimed water is used, it can be dis-posed of only in a manner in which it is ei-ther assimilated into a product (e.g., concretebatch), transpired (e.g., plant uptake), evapo-rated (e.g., cooling tower) or discharged intoa wastewater treatment collection system.

Examples of acceptable uses for reclaimedwater are:

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CASE STUDY

In-Plant Water Reuse

BSH Home Appliances in New Berninstalled a system in its enameling fa-cility that filtered rinse water fromthe parts washer and reused the wa-ter in the first stages of the washer.This water conservation project savedthe facility approximately 2,500 gallonsof water per day of operation. Severaladditional filters were added to thewasher system to keep the water inthe tanks cleaner for longer use, thusreducing the frequency needed todump and clean the tanks.

Soil compactionNon-potable industrial processes such ascooling water concrete productionIndustrial and commercial toilet flushand fire prevention systems where thereare separate, non-potable plumbing linesDecorative ponds and fountainsStreet cleaningVehicle washingCooling tower and boiler make-up

N.C. Environmental Management Commis-sion rules specify criteria that apply to certainuses of reclaimed water as an added controlmeasure to protect public health and the en-vironment. The rules prohibit the use of re-claimed water for irrigation of direct foodchain crops; make-up for swimming pools, spasand hot tubs; and raw water supply.

Bulk distribution of reclaimed water is madeavailable to customers by permitted wastewa-ter treatment facilities. Contact the local pub-lic works department to see if your public util-ity service provider has been approved to dis-tribute reclaimed water.

Industrial effluents meeting reclaimed watereffluent standards can be permitted by theN.C. Division of Water Quality Aquifer Pro-tection Section, Land Application Unit, inorder to beneficially use the effluent outsideof the industry’s process. The rules also haveprovisions to allow for the distribution of sucha reclaimed water effluent to other entities.

For additional information about water reuse,reclaimed water and rule language in the“Waste Not Discharged to Surface Waters”subchapter, see the N.C. Division of WaterQuality Aquifer Protection Section, LandApplication Unit’s Web page at:http://h2o.enr.state.nc.us/lau/main.html.

CASE STUDY

In-Plant Process Water Reuse

Jackson Paper in Sylva manufacturescorrugated cardboard medium from100 percent recycled feedstock. Anon-site wastewater facility allows100,000 gallons of wastewater per dayto be reused on-site. Treated mill wa-ter is reused for papermaking, boilerscrubber make-up water and sludgepress showers in the wastewatertreatment area. No wastewater is dis-charged from the facility. The inten-sive water reuse modifications save anestimated $92,000 per year.

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LANDSCAPING

Landscape Water Use

Starting From ScratchWhen considering a new or revised project,keep in mind these practical steps to get anattractive and low water use landscape:

In North Carolina, outdoor water use annu-ally averages 20-30 percent of the total waterused in a facility. This amount can peak dur-ing the summer growing season up to 70 per-cent. North Carolina’s rainfall is generally con-sistent throughout the year with no pro-nounced wet or dry seasons. Thirty years ofrecords show that everywhere in the state getsbetween 40 and 60 inches of rain a year. Land-scape irrigation is used to supplement this rain-

fall. Based on historical averages, supplemen-tal watering of the landscape would be re-quired about 20 percent of the time. Averagesare notoriously fickle so this section will re-view ways to plan, plant and maintain a wa-ter-efficient landscape.

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(A) Planning and DesignA comprehensive design plan is the initialstep to a water-efficient landscape. A well-thought out and researched design willminimize cost and attain a proper strategyfor plant and sprinker placement. These fac-tors should be considered:

Site conditions such as drainage, soiltype, sun exposure/shade, aestheticpreferences, existing plantings, slope/grade and water availability are all cru-cial elements of an efficient plan.Intended use of the site must be care-fully considered, including recreation,habitat and traffic.Trees, shrubs and grass all require dif-ferent amounts of water. Plants shouldbe placed in groups according to theirrespective water needs, calledhydrozones. This way, an irrigation sys-tem can be designed to properly matchthe needs of the plants, soils and weatherconditions.A proper irrigation design should havea base calculated schedule that includesprojected sprinkler run times and weeklyfrequency for each month of the grow-ing season. This base schedule is usedas a starting point for an irrigation man-ager.Incorporate high water demandingplants at the bottom of slopes.Incorporate the use of existing trees,plants and wildlife areas to help addvalue to the site.Consider creating shade areas, whichcan be 20 degrees cooler than non-shaded areas.Minimize the use of impervious surfacesto reduce runoff and subsequentstormwater pollution.Consider using porous materials suchas porous concrete or permeable pavingmethods.Consider grading and directing surfacerun-off and rainfall gutters to landscaped

areas as opposed to drainageways thatexit the property.

(B) Soil Analysis andImprovement

Soil testing will help determine soil qual-ity, nutrients present and absorptive ca-pacity. Choose plants based on thesefindings. Most soils require some adjust-ment of the pH (acidity or alkalinity).Your county cooperative extension of-fices can provide more informationabout how to conduct soil testing. TheN.C. Department of Agriculture andConsumer Services provides free soiltesting and improvement recommenda-tions.Organic matter such as compost, mulchor manure increases the water holdingcapacity of soil and can help improvewater distribution.When improving the soil of a given area,it is important to treat a large areaaround the planting to allow amplespace for root systems.Do not allow heavy construction equip-ment to compact soil around existingtrees or other sensitive natural areas.

FIGURE 4-14

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(C) Proper Plant SelectionThe selection of native species cangreatly reduce maintenance costs.Consider plants’ water demand, pest tol-erance, soil nutrient and drainage re-quirements.Native species are adapted to work to-gether in similar soils and benefit eachother’s growth by forming symbiotic re-lationships.

(D) Practical Turf AreasTurfgrass has the highest water con-sumption of any plant group. Typically,turf in North Carolina requires one inchof water per week.Plant grass only where it will provideoptimal functional and aesthetic ben-efits.Avoid very small turf areas under 10 feetwide.Proper watering of turf (less frequentand deeper vs. frequent and light water-ing) will promote deep root develop-ment, which will make the turf moredrought resistant.Turfgrass should be cut to the maximumrecommended height for its type, gen-erally a minimum of two inches to amaximum of four inches for optimumwater use.Whenever possible, plant alternativegroundcovers that require less water, orconsider the use of patios and decks,further reducing water demand.

(E) Efficient IrrigationThe proper design, installation andmaintenance of both the irrigation sys-tem and the landscape will lead to effi-cient irrigation. No amount of goodmaintenance can overcome the ineffi-ciencies of poor design.Additional irrigation will be needed onnewer transplanted landscapes.Automatic controllers are a cost-effectivetime-based method to save labor andconsistently deliver water. It is importantto adjust controllers regularly forweather changes and plant growth.Drip irrigation and microsprays placewater at the base of the plant. This re-duces evaporation and saves water by notwetting the entire ground surface. Thistechnique is good for trees, shrubs andground covers.Uniformity of the water being appliedby the irrigation system is the key ingre-dient in irrigation efficiency. Sprinkleruniformity is affected by the operatingpressure, the nozzle used and the sprin-kler spacing, as well as external forcessuch as wind.Plants transpire moisture through theirleaves and the soil allows water to evapo-rate into the air. This condition is calledevapotranspiration. Replacing the plant’sET will allow the plant to thrive. Rain willreplace some of the moisture, irrigationwill do the rest. Tenisometers measure soilmoisture in a plant’s root system. Themeasurement is very close to ET and apractice tool to use when needing to knowhow much irrigation is necessary.Rain shut-off devices on automatic sys-tems cut off the power to the controllerduring rain events and won't allow thesystem to operate until the unit has driedout and irrigation may be needed again.Overspray that covers concrete or otherimpervious areas can waste water by run-ning off the property.

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Xeriscape, Water-Wise, Water-Smartor Low-Water Landscapes

All of these words are used to describe a planfor landscapes that seek to use native plants orlow-water use plants to reduce water demand,lower maintenance requirements with little orno reliance on lawn and garden chemicals.Xeriscape, from the Greek word Xeros, whichmeans to dry, originated in Denver in the early80s. The concept is valid in the humid east, butthe word Xeriscape has a more western con-notation; therefore, water-wise, water-smart or low-water are synonymouswords used in North Carolina. The planning principles mentioned in this chapterare the foundation of a water-wise landscape.

(F) Use MulchesMulches are various organic materials, suchas pine/oak bark, pine straw, aged wood chipsand compost mixtures that are placed aroundthe root zone of a plant.

The use of mulches around planting ishighly effective in retaining soil moistureand reducing the need for watering andmaintenance.Three to five inches of mulch reducesthe level of evaporation from the soil,insulates root systems from heat and lim-its the germination of weeds aroundbeds and flora.Fine textured mulches help retain moremoisture than coarse mulches.

(G) Proper MaintenanceThe most crucial element in sustaining waterefficiency in any landscape site is ensuring thata regular maintenance schedule is met. Atten-tion to the landscape and irrigation system atregular time intervals will lower the cost ofmaintenance, and increase the effectivenessof water for landscaping.

Mow grass at a proper height. No morethan one-third of the leaf blade shouldbe removed during mowing.Regular aeration of clay soils will im-prove water holding capabilities and pre-vent runoff.Monitor irrigation schedules to replaceevapotranspiration.Analyze the soil several times during theseason to be sure nutrient levels aremaintained.Inspect, adjust and replace sprinkers, fil-ters, valves and emission devices forproper operation once a month.

Over-watering landscapes is a more com-mon problem than under-watering.People tend to think that if a little isgood, a lot is even better.

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CASE STUDY

Planning Receives Recognition

The town of Cary has received na-tional recognition for its water conser-vation activities. The town has donecomprehensive water planning to mapits future requirements. It has set uppublic education programs, school les-sons aimed at teaching children aboutwater conservation and a local blockleader program that gets the wholecommunity involved. Cary has insti-tuted a permanent alternative daywatering ordinance, a water wasteordinance and passed a rain sensorordinance. This central North Caro-lina town was one of the first to offerreclaimed water for outdoor irrigationuses and now has 10.4 miles of dedi-cated distribution lines providing176,000 gallons per day for this pur-pose. Conservation pricing in its wa-ter rates and irrigation system auditsare also some of the tools the townused to reduce water consumption.Cary’s active leadership is viewed as amodel for North Carolina local gov-ernments.

BenefitsBenefits of ecologically-based, water-conserv-ing landscapes include:

Reduced off-site water consumption.Lower HVAC requirements.Provision for pedestrian movement andhabitat needs.Maintained nutrients on site.Lower energy use and pollution.

Reduced water pumping and water treat-ment.Lessened runoff of stormwater and irri-gation water.Lower maintenance and labor costs.Increased quality of landscape and sur-rounding habitat.

Tips For ExistingLandscapesPractical steps can be taken to reduce wateruse and improve plant conditions in maturelandscapes with a little effort and attention todetail. Managing an irrigation system is muchlike the management of other mechanicaldevices. Proper settings, operation and main-tenance equate to proper results. Understand-ing the system is the first step. Locate the origi-nal design of the system and check it againstthe system that is actually on the property.Significant changes may have been made overthe years to the facilities that make what wasoriginally installed much less efficient. Out-side professional assistance may be warrantedin this review stage. The Irrigation Associa-tion tests and certifies individuals in variousspecialties such as design, contracting, watermanagement and system auditing. NorthCarolina individuals with these certificationscan be located on the association’s Web siteat http://www.irrigation.org.

How to WaterWater in the early morning or lateevening to maximize absorption andminimize evaporationWater only when wind is less than 10miles an hour.Peak water demand occurs with summertemperatures and plant demand is muchlower in the spring and fall seasons.Be sure irrigation system is balanced,especially in turf areas. A balanced ormatched system provides the same pre-cipitation rate whether using a quarter

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FIGURE 4-15inch circle pop-up spray head or afull circle rotor type sprinkler. Thereis an old adage that everyone watersto take care of the dry spot. If thesystem is in balance no dry spotsappear and the balance, of the turfis not over-watered.Use evapotranspiration data to helpdetermine the plant’s water needs.N.C. State University’s Web site“Turfgrass Irrigation ManagementSystem,” provides information aboutET demand and the irrigation re-quirements of N.C. turfgrasses(http://www.TurfFiles.ncsu.edu/TIMS).Measure the amount of rainfall at vari-ous locations throughout the facility.Maintain a record of this rainfall andadjust the operating time of the irriga-tion system to replace the ET minus theweekly rainfall. This is sometimes calledthe “checkbook” method.Alternatively, use tensiometers whichmeasure soil moisture; set the control-ler to replace the water needed to bringthe tensiometer gauge to “moist.”Water once or twice a week using anautomatic sprinkler system. Drip irriga-tion requires more frequent longer du-ration runs.Note any areas where the sprinklers areover-spraying buildings, sidewalks orpavement and adjust the spray patternto avoid these areas. A system that waspoorly designed initially will immedi-ately give itself away by wateringhardscape areas.

Amount of Water PlantsRequire

Use evapotranspiration data to help de-termine a plant’s water needs.Water deeply once or twice a week in-stead of lightly every day. (See Figure 4-15.)To prevent runoff or deep percolationbelow the roots, never apply water fasterthan the soil can take it in or more thanthe soil can hold. (See Figure 4-16, nextpage.)Assess the characteristics of a sitethrough a water audit. Audits evaluatethe specific water needs and conditionsof an existing site.Consider that every square foot of wa-tershed hardscape can shed more than25 gallons of irrigation water every year.

Check Out These N.C.-based Landscaping Links

Going Native: Urban Landscaping for Wildlife with Native Plants -http://www.ncsu.edu/goingnative/index.html

TurfFiles - http://www.turffiles.ncsu.edu/Default.aspx

Industrial/Commercial Horticultural Information Leaflets -http://www.ces.ncsu.edu/depts/hort/hil/landscape-index.html

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Sprinkler TypeSoil Type Spray Rotor

Maximum SprinklerRun Time

Minutes Per Application

Sand 15 to 20 45 to 60Loam 10 to 15 30 to 45Clay 7 to 10 20 to 30

System MaintenanceConsiderations

Use the same size nozzle when replace-ment is needed.Replace sprinklers with the same brandof sprinklers. Spray heads should notoperate on the same valve with rotors.Ensure spray heads are aligned withgrade.Replace worn spray nozzles.Regulate pressure properly for systemdemands.Many times a rotor or spray head will bemounted incorrectly in an attempt tocover a greater area. Replace with properunit for the job.Post the current controller schedule in-side the door of the controller.Check for leaking valves.Inspect low-volume emitters for any stop-page.Inspect sprinklers for clogged nozzleswhich distort the spray pattern.Adjust sprinklers to water plant mate-rial and not sidewalks or roads.Adjust the operating time (runtimes) ofthe sprinklers to match the seasonal ormonthly requirements.Monitor plant leaves and take soilsamples to confirm proper system opera-tion.

Irrigation SystemOperations

Consider adding a rain shutoff deviceto your automatic irrigation control sys-tem.Consider alternative sources for irriga-tion water, including the use of wells asopposed to city water, water reuse op-tions from air conditioning condensate,storm water retention ponds, cisterns ornon-contact cooling water.Reclaimed water from the local watertreatment facility may be available for useat a lower cost.Use electronic controllers with precise tim-ing, multiple irrigation zones, multiplecycles and attached rain shut-off devices.Incorporate separate irrigation zones forall irrigated plant hydrozones, and useseparate irrigation zones for turf areas.Use dedicated water meters for landscap-ing water use.Use drip or other low volume irrigationwherever possible.Have a catchment, or distribution uni-formity, test performed on-site to deter-mine how evenly water is applied whensprinklers are in use.

Water SupplyExpectationsMost landscape irrigation systems use potablewater supplied by the local water purveyor.These firms are in the conflicting business ofselling water and sheparding local water re-sources at the same time. When dry periodsoccur and demand accelerates, the water pur-veyors must limit access to their finite resource.Most have policies in effect as to what stepswill take place in water-short periods. Thesepolicies may include limiting outdoor water-ing to certain days a week, increasing rates onhigh water users or barring outdoor water usealtogether. It is important to know what to

FIGURE 4-16

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Untreated Gray Water

The North Carolina Plumbing Code defines gray water as “waste discharged fromlavatories, bathtubs, showers, clothes washers, and laundry sinks.” The disposal ofsewage/wastewater is regulated by North Carolina law, which can be found online athttp://www.deh.enr.state.nc.us/osww_new/new1//images/Rules/1900RulesJune2006.pdf.

15NCAC 18A.1935 Definitions: “Sewage” means the liquid and solid human wasteand liquid waste generated by water-using fixtures and appliances, including thoseassociated with food handling. The term does not include industrial process wastewa-ter or sewage that is combined with industrial wastewater.

expect in a drought emergency, so check withyour local water purveyor to see what plans ithas in place.

Many jurisdictions can provide reclaimed wa-ter (treated effluent water suitable for plants)that can be obtained through a contract withthe purveyor. Separate pipelines are neededto get this water to your facility and this infra-structure problem may be the prime obstacle.If reclaimed water is available, it is generallylower cost and available in periods of waterstress.

Water EfficientTechnologiesAutomatic Irrigation Timer

A simple-to-operate automatic timer or con-troller can be installed on an existing manualirrigation system. The controller automaticallywill operate the sprinklers on the proper dayof the week for the correct amount of runtime. This will meet the plant’s water needsas well as apply the water in off-peak night orearly morning hours. More elaborate control-lers offer extra flexibility to manage larger siteswith many different hydrozones and site con-ditions. Any controller can use a rain or soilmoisture sensor to prevent the sprinklers fromoperating when natural precipitation has metthe plants’ water needs.

CASE STUDY

Rainwater Cisterns

UNC-Chapel Hill installed a 70,000-gallon underground cistern and gravelstorage field at a sports field on cam-pus. The cistern system captures rain-water from the roofs of nearby build-ings, and stores the water until it isused to irrigate the field. Various othercistern systems on UNC-CH’s cam-pus, can be used for both irrigation andflushing toilets.

“Smart” Controllers

A new class of “smart” controllers is now avail-able on the market. Unlike traditional con-trollers, which are really just timers, “smart”controllers work by monitoring and using in-formation about site conditions (such as soilmoisture, rain, wind, slope, soil, plant type andmore), and applying the right amount of wa-ter based on those factors. These climate based“smart” controllers are avialable from manymanufacturers and the irrigation industry hascreated an evaluation program to set standardsof performance for this class of product.

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Centralized Irrigation Controllers

To manage many irrigation controllers spreadout among many sites, a centralized controlsystem will save labor costs as well as increasewater efficiencies. A typical central irrigationcontrol system utilizes a computer to create,adjust and save irrigation schedules for mul-tiple controllers at various locations. The com-puter then communicates to the controllersby radio, hardwire, telephone or a combina-tion of two or more methods. A computer-central system can also monitor and react todifferent alarm situations like broken headsor pipes, valve malfunctions or many otherwater-saving sensors.

A central control system does not relieve thewater manager from monitoring and adjust-ing the equipment. It allows them to quicklyadjust multiple controllers to the monthly ordaily changes in conditions that affect thewater needs of the plants. These units can beeconomically justified for larger and multiplesite operations.

PC Software

Software programs have been developed to as-sist the designer and water manager in the analy-sis of the efficiency of an existing or newly-de-signed irrigation system. Two of the primaryprograms were developed by the Center for Ir-rigation Technology at California State Univer-sity, Fresno. The program used to generategraphic representations of sprinkler efficienciesis called Hyper-SPACETM. The software that ana-lyzes the costs versus the benefits of improvingirrigation efficiencies is called SPACE IrrigationSurveyTM. Many certified water auditors and cer-tified irrigation designers use these softwareprograms extensively.

CASE STUDY

Wastewater Reuse

Aurora, Colo., eliminated more thanone billion gallons of water needs bythe construction of a wastewater re-claimed system that uses industrialwastewater for irrigation.

New Sprinkler Type

Install a multi-trajectory rotating stream sprin-kler with high application uniformity. Thisfriction resistance head operates at lower pres-sures and fills the product range between sprayheads and rotors.

Flow Control Nozzles

Sprinklers with a uniform application rate thatuse the lowest possible water pressure are thegoal. One method that helps achieve this goalis the use of flow-control nozzles. Each sprin-kler nozzle is equipped with a flow-controldevice that compensates for flow changes andmaintains a uniform pressure. This can be adesirable feature on slopes. The flow controlalso acts to reduce flow should a sprinklerhead be broken.

Sensors

Several types of sensors are available that takethe human factor out of irrigation system op-eration.

Rain shut-offsFreeze sensorsWind sensorsFlow sensorsSoil moisture measurementWeather stations

Rain shut-offs have the single largest impacton water savings in automatic irrigation.North Carolina has regular and balancedrains, making this sensor a valuable tool as itcuts off the controller when a pre-set rain levelis reached. When the weather conditions dryout, the rain shut-off allows the controller toresume normal operation without affectingthe programming of the controller.

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Freeze sensors are specialized sensors that stopall irrigation when a pre-set temperature isreached.

Wind sensors cut off irrigation as wind ve-locities reach certain levels. This sensor wouldbe most commonly used in coastal areas orwhere wind velocities vary throughout thegrowing season.

Flow sensors respond to high flow situationscaused by broken sprinkler heads or a pipe-line break. The sensor shuts off the irrigationuntil repairs can be made. This is especiallyimportant on hillsides that could wash away.

Soil moisture measurement sensors are devicesthat measure soil/water tension and functionas an artificial root. These devices can use vari-ous methods to report soil moisture, includ-ing tensiometers, gypsum blocks and electri-cal resistance devices. All are designed to sig-nal when there is not enough moisture in theroot zone of a plant. The sensors can activate

Water-Efficient PlantsA major factor of water-efficient landscapes isthe selection of plants. Plants’ watering needsare divided by hydrozones. The use of drought-tolerant and native plants not only minimizesrunoff concerns, but also can strategicallymake the most use of rainfall patterns. In ad-dition to the lists of drought-tolerant plants(see next two pages), the N.C. Cooperative Ex-tension Service can provide further informa-tion and assistance for selecting water-efficientplants.

a control device such as a valve or controllerto turn on.

Weather stations that are situated at a facilityinclude all of the sensors mentioned plus datalogging of weather conditions at the site. On-site weather stations can record and advise“smart” controllers about real time local con-ditions.

T R

E E

S B

y

C

Common Name Botanical Name

Lacebark elm Ulmus parvifoliaJapanese zelkova Zelkova serrataTulip poplar Liriodendron tulipferaSycamore Platanus occidentalisLaurel oak Quercus lauifoliaLive oak Quercus virginianaPin oak Quercus palustrisWhite oak Quercus albaCrepe myrtle Lagerstroemia indicaHollies Ilex spp.Chaste tree Vitex agnus-castusSweet gum Liquidambar styraciflua

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S H

R U

B S Common Name Botanical Name

Chinese photinia Photinia serrulataElaeagnus ElaeagnusFirethorn Pyracantha coccinea

(pyracantha)Japanese privet Ligustrum japonicumJunipers Juniperus spp.Yaupon holly Ilex vomitoriaMahonia Mahonia spp.Nandina Nandina domesticaChinese holly Ilex cornutaStrawberry bush Euonymus americanaForsythia Forsythia intermediaBarberry Berberis spp.Quince Chaenomeles japonicaViburnum Viburnum spp.Euonymus Euonymus spp.Spirea Spirea spp.Glossy abelia Abelia grandifloraJasmine Jasminum spp.

e

d

d

GR

OU

ND Common Name Botanical Name

Mondograss Ohpiopogon japonicusLiriope Liriope spp.Junipers Juniperus spp.Thrift Phlox subulataEnglish ivy Hedera helixClematis Clematis spp.Trumpet honey Lonicera sempervirens

suckleWisteria Wisteria spp.Wintercreeper Euonymus fortuneiPeriwinkle Vinca spp.

COVERS/VINES

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AN

NU

AL

SCommon Name Botanical Name

Gazania Gazania rigensAnnual vinca Catharathus roseusAnnual phlox Phlox drummondiiBaby’s breath Gypsophila spp.Black-eyed Susan Rudbeckia spp.Coreopsis Coreopsis spp.Cape marigold Dimorphotheca sinuataCornflower Centaurea cyanusCosmos Cosmos spp.Globe amaranth Gomphrena globosaMoss rose Portulaca grandifloraStraw flower Helichrysum bacteatumVerbena Verbena spp.Butterfly weed Asclepias tuberosaGaillardia Gaillardia x grandifloraGoldenrod Solidago hybridsLiatris Liatris spp.Purple coneflower Echineacea purpureaSedum Sedum spp.Stokes’ aster Stokesia cyanea

PERENNIALS&

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Wool 13.3 34.1 78.9

Woven 0.6 13.6 60.9

Knit 2.4 10.0 45.2

Carpet 1.0 5.6 19.5

Stock/Yarn 0.4 12.0 66.9

Nonwoven 0.3 4.8 9.9

Felted Fabrics 4.0 25.5 111.8

5 Industry SpecificProcesses

Textiles

Food & Beverage

Metal Finishing

T E X T I L E S*

*Excerpts from “Best Management Practices for Pollution Prevention in the Textile Industry,” EPA, 1996.

Water Use in Textile ProcesingWater Use Water Use Water Use

Processing Minimum, gal/lb Median, gal/lb Maximum, gal/lbSubcategory of production of production of production

FIGURE 5-1

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Water Consumption inTextilesWater is used extensively throughout textileprocessing operations. Almost all dyes, spe-cialty chemicals and finishing chemicals areapplied to textile substrates from water baths.Most fabric preparation steps, includingdesizing, scouring, bleaching and mercerizing,use aqueous systems. In addition, there aremany washing steps in textile manufacturing.

The amount of water used varies widely inthe industry, depending on the specific pro-cesses operated at the mill, the equipmentused and the prevailing management philoso-phy concerning water use. Reducing waterconsumption in textile processing is impor-tant for furthering pollution prevention ef-forts, in part because excess water use dilutespollutants and adds to the effluent load.

Mills that currently use excessive quantitiesof water can achieve large gains from pollu-tion prevention. A reduction in water use of10 to 30 percent can usually be accomplishedby taking fairly simple measures. A walk-through audit can uncover water waste in theform of:

Hoses left running.Broken or missing valves.Excessive water use in washing opera-tions.Leaks from pipes, joints, valves andpumps.Cooling water or wash boxes left run-ning when machinery is shut down.Defective toilets and water coolers.

In addition, many less obvious causes of wa-ter waste exist. These causes are presentedbelow by subcategory, unit process and ma-chine type.

SubcategoryTextile operations vary greatly in water con-sumption. Figure 5-1 summarizes the waterconsumption ranges observed in an extensivestudy of various types of operations. Wool andfelted fabrics processes are more water inten-sive than other processing subcategories suchas wovens, knits, stock and carpet.

Water use can vary widely between similaroperations as well. For example, knit millsaverage 10 gallons of water per pound of pro-duction, yet water use ranges from a low of2.5 gallons to a high of 45.2 gallons. Thesedata serve as a good benchmark for determin-ing whether water use in a particular mill isexcessive.

Unit ProcessWater consumption varies greatly among unitprocesses, as indicated in Figure 5-2. Certaindyeing processes and print after-washing areamong the more intensive unit processes.Within the dye category, certain unit processesare particularly low in water consumption (e.g.,pad-batch).

Machine TypeDifferent types of processing machinery usedifferent amounts of water, particularly in re-lation to the bath ratio in dyeing processes(the ratio of the mass of water in an exhaustdyebath to the mass of fabric). Washing fab-ric consumes greater quantities of water thandyeing. Water consumption of a batch pro-cessing machine depends on its bath ratio andalso on mechanical factors such as agitation,mixing, bath and fabric turnover rate (calledcontact), turbulence and other mechanicalconsiderations, as well as physical flow char-acteristics involved in washing operations.These factors all affect washing efficiency.

In general, the major energy uses in dyeingare (1) preparation of fabric for dyeing (wash-

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Water Consumption by Unit Process

Processing Water Consumption,Subcategory gal/lb of Production

Yarn & fabric forming Nil

Slashing 0.06 to 0.94

Preparation

Singeing Nil

Desizing 0.3 to 2.4

Scouring 2.3 to 5.1

Continuous bleaching 0.3 to 14.9

Mercerizing 0.12

Dyeing

Beam 20

Beck 28

Jet 24

Jig 12

Paddle 35

Skein 30

Stock 20

Pad-batch 2

Package 22

Continuous bleaching 20

Indigo dyeing 1 to 6

Printing 3

Print afterwashing 13.2

Finishing

Chemical 0.6

Mechanical Nil

FIGURE 5-2

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ing, bleaching, etc.), (2)heating dyebaths andwash water, and (3) dry-ing goods after dyeing.Therefore, low bath-ratiodyeing equipment notonly conserves water butalso saves energy, in ad-dition to reducing steamuse and air pollutionfrom boilers. Low-bath-ratio dyeing machinesconserve chemicals aswell as water and alsoachieve higher fixationefficiency. But the wash-ing efficiency of sometypes of low-bath-ratiodyeing machines, such asjigs, is inherently poor;therefore, a correlationbetween bath ratio andtotal water use is not al-ways exact.

Reusing Non-processCooling Water

Process WaterConservationWashingWashing and rinsing operations are two of themost common operations in textile manufac-

Saturators 550 5

Steamer and J Boxes 150 1.4

Washers

Desize 3,700 33.5

Scour 3,100 28.1

Bleach 3,100 28.1

Dry Cans 450 4.1

TOTAL 11,050 100

Water Consumptionfor a Typical Bleach Range

Stage Water, gph Percent

FIGURE 5-3

Perhaps the easiest of all water recycle activi-ties is to plumb the once-through non-contactcooling water back to the clean well (or waterinfluent). This water requires little or no treat-ment as it’s not contaminated from processchemicals. Also, be sure to stop the coolingwater when the machine is stopped and tolimit the amount of cooling water when themachine is on. It is very common to find wa-ter-cooled bearings, heat exchangers, etc.withvery excessive flow rates.

turing that have significant potential for pol-lution prevention. Many processes involvewashing and rinsing stages, and optimizingwash processes can conserve significantamounts of water. In some cases, careful au-diting and implementation of controls canachieve wastewater reductions of up to 70percent. The washing and rinsing stages ofpreparation typically require more water thanthe other stages (e.g., bleaching, dyeing). Sev-eral typical washing and rinsing processes in-clude:

Drop and fill batch washing.Overflow batch washing.Continuous washing (countercurrent,horizontal or inclined washers).

A report on water consumption for a typicalcontinuous bleach range found that consump-tion was more than 11,000 gallons per hour,or 270,000 gallons per day (see Figure 5-3).Washing stages accounted for 9,900 gallonsper hour, or 90 percent of the total. The ap-plication of the following simple, low-technol-

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ogy methods of water conservation reducedwater use:

Properly regulating flows: 300 gallonsper hour savings.Counterflowing bleach to scour: 3,000gallons per hour savings.Counterflowing scour to desize: 3,000gallons per hour savings.Shut off water flow when machine isstopped.

The total water savings without process modi-fication was 150,000 gallons per day, or 55percent of water use. A process modificationsuch as a combined one-stage bleach and scouralso would save 6,200 gallons of water perhour, or an additional 150,000 gallons per day,along with energy savings.

One of the critical points in water conserva-tion for washing processes is stopping the pro-cess at the appropriate time. Factories oftenhave very specific procedures for dyeing pro-cesses but vague specifications for washing. Inaddition, washing processes are often exces-

sively long to ensure completeness. This en-sures that the darkest shades are adequatelywashed, but may result in excessive water andenergy use for lighter shades that do not re-quire extended washing.

Water Use in Batch WashingProcess Water Use, Percent ChangeDescription Bath Ratio gal/lb from Standard

FIGURE 5-4

1. Standard - 3 step 1:8 1.62 --

drop/fill

2. Reduced bath - 7 step

drip/fill 1:5 1.26 -22.2

3. Continuous overflow 1:8 2.38 46.9

4. Continuous overflow -

reduced bath 1:5 1.49 -8

5. 3 step drop/fill,

reuse bath 2 1:8 1.19 -26.5

6. 3 step, reuse

baths 2 and 3 1:8 0.75 -53.7

Drop-Fill Vs.Overflow WashingIn the drop/fill method of batch washing,spent wash water is drained and the machineis refilled with a fresh wash bath. The fabricor other substrate in the machine retains muchof the previous bath, perhaps as much as 350percent onweight of goods. This percentagecan be reduced by mechanical means (e.g., ex-traction, blowdown). Comparison of severalmethods of washing after bleaching shows thebenefits of countercurrent wash methods (seeFigure 5-4). Methods five and six, which imple-ment countercurrent washing, produce sav-ings of 26 and 53 percent compared with thestandard drop/fill method. These results arebased on comparisons of washing processesthat would produce the same degree of reduc-tion of fabric impurities using computer mod-els.

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Countercurrent washing processes require theaddition of holding tanks and pumps. Thecapital cost of setting up such a reuse systemtypically is less than $50,000 and generatesestimated savings of $95,000 annually. Inmany cases, reducing wastewater also reducesthe need for expensive waste treatment sys-tems.

Reusing Wash WaterMany strategies can be applied for reusingwash water. Three of the most common strat-egies are countercurrent washing, reducingcarryover and reusing wash water for clean-ing purposes.

Countercurrent Washing

Reducing CarryoverBecause the purpose of washing is to reducethe amount of impurities in the substrate, asmuch water as possible must be removed be-tween sequential washing steps in multistagewashing operations. Water containing con-taminants that are not removed is “carriedover” into the next step, contributing to wash-ing inefficiency.

Proper draining in batch drop/fill washingand proper extraction between steps in thecontinuous washing process are important.Often, 350 percent on weight of goods is car-ried over in typical drop/fill procedures. Thisamount can be reduced in some batch ma-chines (e.g., yarn package dyeing, stock dye-ing) by using compressed air or vacuumblowdown between washing steps.

In continuous washing operations, squeezerolls or vacuum extractors typically extractwater between steps. Equipment employingvacuum technology to reduce dragout andcarryover of chemical solutions with cloth,stock or yarn is used to increase washing effi-ciency in multistage washing operations.

In one case history, a processor installedvacuum slots after each wash box in an exist-ing multistage continuous washing line andwas able to reduce the number of boxes fromeight to three. Wash boxes with built-invacuum extractors are available for purchase,as well as washers for prints that combine suc-cessive spray and vacuum slots without anybath for the fabric to pass through. Becausethe fabric is never submerged, bleeding, mark-ing off and staining of grounds is minimized,and water use decreases.

Another washer configuration with internalrecycling capabilities is the verticalcounterflow washer, which sprays recirculatedwater onto the fabric and uses rollers tosqueeze waste through the fabric into a sump,where it is filtered and recirculated. The filter

The countercurrent washing method is rela-tively straightforward and inexpensive to usein multistage washing processes. Basically, theleast contaminated water from the final washis reused for the next-to-last wash and so onuntil the water reaches the first wash stage,after which it is discharged. This technique isuseful for washing after continuous dyeing,printing, desizing, scouring or bleaching.

An important variant of the countercurrentprinciple is “horizontal” or “inclined” wash-ers. Horizontal or inclined washing is moreefficient because of the inherent countercur-rent nature of water flow within the process.The mechanical construction of an inclinedor horizontal countercurrent washer has to bemuch better than a traditional vertical washer,however.

Sloppy roll settings, weak or undersized rolls,unevenness, bends, bows, biases, bearing playor other misalignments within the machineare much more important in a horizontal orinclined washer because the weight of waterpressing down on the fabric can cause it tosag, balloon or stretch. If properly constructedand maintained, horizontal or inclined wash-ers can produce high quality fabrics while sav-ing money and water.

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is unique, consisting of continuous loops ofpolyester fabric that rotate continuously andare cleaned of filtrate at one end with a sprayof clean water. This construction allows formaximum removal of suspended solids fromwater before discharge or reuse in anotherprocess. High-efficiency washing with lowwater-use results. Energy use decreases greatlybecause less water must be heated.

Reuse for Cleaning Purposes

In many types of operations, washwater canbe reused for cleaning purposes. In printing,cleanup activities can be performed with usedwashwater, including:

Backgray blanket washing.Screen and squeegee cleaning.Color shop cleanup.Equipment and facility cleaning.

A typical preparation department may alsoreuse wash water as follows:

Reuse scour rinses for desizing.Reuse mercerizer washwater for scour-ing.Reuse bleach washwater for scouring.Reuse water-jet loom washwater fordesizing.Recycle kier drains to saturator.

Work Practices

Engineering ControlsEvery mill should have moveable water metersthat can be installed on individual machinesto document water use and evaluate improve-ments. In practice, mills rarely measure wateruse but rely on manufacturers’ claims concern-ing equipment and water use. The manufac-turers’ estimates are useful starting points forevaluating water consumption, but the actualperformance of equipment depends on thechemical system used and the substrate. There-fore, water use is situation-specific and shouldbe measured on-site for accurate results. Thewater meters should be regularly maintainedand calibrated.

Other important engineering controls, someof which have been discussed in other sectionsof this chapter, include:

Workers can greatly influence water use.Sloppy chemical handling and poor house-keeping can result in excessive cleanup. Poorscheduling and mix planning also can requireexcessive cleanup and lead to unnecessarycleaning of equipment like machines and mixtanks. Leaks and spills should be reported andrepaired promptly. Equipment maintenance,especially maintenance of washing equipment,is essential. Inappropriate work practices wastesignificant amounts of water; and good pro-cedures and training are important. Whenoperations are controlled manually, an opera-tions audit checklist is helpful for operatorreference, training and retraining.

In one case history, a knitting mill experiencedexcessive water use on beck dyeing machines.A study of operating practices revealed thateach operator was filling the machines to adifferent level. Some operators filled the becksto a depth of 16 inches, others as much as 24inches. Also, the amount of water used forwashing varied. Some operators used an over-flow procedure, and others used drop/fill or“half baths” (repeatedly draining half of thebath, then refilling it).

Inspection of the written procedures showedthat the fill step simply said “fill.” The washstep simply said “wash.” Without training andwithout a specific operating procedure, opera-tors were left to determine water use on theirown. This case may seem extreme, but eventhe best mills, which have well-documentedproduction procedures, often do not havedocumented cleaning procedures. Cleaningoperations that contribute large amounts ofpollution to the total waste stream includemachine cleaning, screen and squeegee clean-ing and drum washing.

Flow control on washers.

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Flow control on cooling water (use mini-mum necessary).Countercurrent washing.High extraction to reduce dragout.Recycle and reuse.Detection and repair of leaks.Detection and repair of defective toiletsand water coolers.

Machinery should be inspected and improvedwhere possible to facilitate cleaning and toreduce susceptibility to fouling. Bath ratiossometimes can be reduced by using displacersthat result in lower chemical requirements forpH control as well as lower water use.

Process ChangesPad-Batch Dyeing

In pad-batch dyeing, prepared fabric is paddedwith a solution of fiber reactive dyestuff andalkali, then stored (or batched) on rolls or inboxes and covered with plastic film to preventevaporation of water or absorption of carbondioxide from the air. The fabric then is batchedfor two to 12 hours. Washing can be done onwhatever equipment is available in the mill.

Pad-batch dyeing offers several significant ad-vantages, primarily cost and waste reduction,simplicity and speed. Production of between75 and 150 yards per minute, depending onthe construction and weight of the goods in-volved, is common. Also, pad-batch dyeing isflexible compared with a continuous range.Either wovens or knits can be dyed in manyconstructions. Frequent changes of shadepresent no problems because reactives remainwater soluble, making cleanup easy. Thismethod of dyeing is useful when versatility isrequired. Water use typically decreases from 17gallons per pound to 1.5 gallons per pound, areduction of more than 90 percent.

Processing Bath ReuseWater from many processes can be renovatedfor reuse by a variety of methods. Several re-

search efforts are underway. In a few opera-tions, up to 50 percent of the treated waste-water is recycled directly back from the efflu-ent to the raw-water intake system with noadverse effects on production. In some cases,specific types of wastewater can be recycledwithin a process or department. Examples aredyebath reuse, bleach bath reuse, final rinsereuse as a loading bath for the next lot,washwater reuse, countercurrent washing andreuse for other purposes.

Bleach Bath ReuseCotton and cotton blend preparation (e.g.,desizing, scouring, bleaching) are performedusing continuous or batch processes and usu-ally are the largest water consumers in a mill.Continuous processes are much easier toadapt to wastewater recycling/reuse becausethe wastestream is continuous, shows fairlyconstant characteristics and usually is easy tosegregate from other waste streams.

Waste-stream reuse in a typical bleach unit forpolyester/cotton and 100 percent cotton fab-rics would include:

Recycling J-box and kier drain wastewa-ter to saturators.Using countercurrent washing.Recycling continuous scour washwaterto batch scouring.Recycling washwater to backgray blan-ket washing.Recycling washwater to screen andsqueegee cleaning.Recycling washwater to color shopcleanup.Recycling washwater to equipment andfacility cleaning.Reusing scour rinses for desizing.Reusing mercerizer washwater for scour-ing.

Preparation chemicals (including opticalbrighteners and tints), however, must be se-lected in such a way that reuse does not create

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quality problems such as spotting. Batch scour-ing and bleaching are less easy to adapt to re-cycling of waste streams because streams oc-cur intermittently, drains generally go into pitsand are not easily segregated and batch prepa-ration steps frequently are combined. Withappropriate holding tanks, however, bleachbath reuse can be practiced in a similar man-ner to dyebath reuse, and several pieces ofequipment are now available that have thenecessary holding tanks. The spent bleachbath contains all of the alkali and heat neces-sary for the next bleaching operation. Perox-ide and chelates must be added to reconsti-tute the bath. Like dyebath reuse, the num-ber of reuse cycles in bleach bath reuse is lim-ited by impurity buildup. The main impuri-ties are metals, such as iron, that can interferewith the bleaching reaction.

New types of rope bleaching units for knitsfeaturing six to 12-stage jet transport systemshave made continuous bleaching of most knitstyles possible. These units were introducedin the late 1970s and typically produce 40pounds per minute of knit fabric or more thanone million pounds per month based on athree-shift, six-day operation. These machines

Final Rinse Reuse asLoading Bath for Next LotOne simple technique that saves water and,in some cases, biological oxygen demand load-ing is to reuse the final bath from one dyeingcycle to load the next lot. This technique workswell in situations where the same shade is be-ing repeated or where the dyeing machine isfairly clean.

A good example of this technique is acid dye-ing of nylon hosiery. The final bath usuallycontains an emulsified softener that exhaustsonto the substrate, leaving the emulsifier inthe bath. This technique can serve as the wet-ting agent for loading the next batch, thussaving the water, heat, wetting agent and asso-ciated BOD.

have become very popular with large knit pro-cessors because of their flexibility and abilityto conserve energy, water and chemicals. Theyalso have complete built-in countercurrentcapabilities. These units are being promotedfor use in afterwashing fiber reactive and othertypes of dyes (e.g., after pad-batch dyeing) inaddition to use as continuous knit prepara-tion ranges.

In the food and beverage industry, water playsa significant role in transporting, cleaning,processing and formulating products, as wellas in meeting many federal sanitary standards.Facilities implementing water conservationprograms sometimes struggle to balance these

needs with the many benefits of reducing wa-ter usage. The following section discusses themethods and techniques that many facilitieshave used to implement successful water con-servation programs while maintaining produc-tion requirements.

F O O D B E V E R A G E&Water Conservation Techniques

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For general rinsing and cleaning operations,refer to Chapter 4 on cleaning, rinsing andin-process water reuse. Several opportunitiesin the beverage industry include:

Adjust pumped cooling and flushingwater to the minimum required.Investigate potentially reusable dis-charges, including final rinses from tankcleaning, keg washes and fermenters;bottle and can soak and rinse water;cooler flushwater; filter backwash; andpasteurizer and sterilizer water, as wellas cooler water. Measure these uses toget a baseline inventory for monitoring.Potential areas for reuse include firstrinses in wash cycles; can shredder;bottle crusher; filter backflush; causticdilution; boiler make-up; refrigerationequipment defrost; and floor andgutter wash. Cooler water can be re-treated and reused in many in-stances.

Several opportunities in the food indus-try include:

Rechlorinate and recycle transportwater where feasible.Use conveyor belts for product trans-port. Preference should be given to“rabbit-ear” or V-shaped roller sup-ports because these are much easierto clean.Use pneumatic conveying systemswhere practical.Use flumes with parabolic cross-sec-tions rather than f lat bottomtroughs.Consider these alternatives to water-intensive units: 1) rubber-disc scrub-bing units vs. raw product cleaningand peeling; 2) steam rather thanwater blanchers, or 3) evaporativecoolers rather than water-cooled sys-tems.Establish optimum depth of prod-

uct on conveyors to maximize wash wa-ter efficiency.Optimize nozzle size and pressure.Change eroded and non-functionalnozzles.Divide spray wash units into two or moresections, and establish a counterflow re-use system.Control belt sprays with a timer to al-low for intermittent application of chlo-rinated water.Consider soaking units where indicated.

CASE STUDY

Recycling Transport Water

A food processing facility in St. Paul,Minn., hired an intern to evaluate wa-ter usage in corn processing. For thetransport water use (5,200 gallons perday) the intern investigated alternativedry methods: 1) screw conveyorswere unacceptable because of thedegradation of corn, 2) belt convey-ors on the vertical cook tanks were apotential solution but only reducedwater by 10 percent, making the ini-tial investment unjustifiable. The internfound that 20 percent of the transportwater could be recycled without af-fecting product quality (concerns in-cluded pH and cleanliness). Recycling20 percent would reduce total plantwater usage by 3.5 percent and save$1,570 annually.

Figure 5-5 provides a listing of potential reuseareas for specified canning operations.

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Acid dip for fruit yes no can coolers

Washing of product

First wash, followed by second wash yes yes1 can coolers

Final wash of product no yes1 can coolers

Flumes

Fluming unwashed or unprepared product yes yes1 can coolers

Fluming partially prepared product yes yes1

Fluming fully prepared product no yes any wastewater

Fluming waste yes no can coolers

Lye peeling yes no

Product holding vats (covered with water or brine) no no

Blanchers, all types

Original filling water no no

Replacement of make-up water no no

Salt brine quality graders with fresh water final wash yes this operation

Washing pans and trays

Tank washers, original water no no

Spray or make-up water no no

Lubrication of product inside machines no yes1 can coolers

Washing cans after closing no no

Brine and syrup yes yes1 can coolers

Processing jars and underwater no

Can coolers yes this operation can coolers

Cooling canals

Original make-up no yes2

Make-up water yes yes2

Continuous cookers (cans partially immersed)

Original make-up no yes2

Make-up water yes yes2

Spray coolers with cans not immersed yes yes

Batch cooling in retorts yes yes2

Clean-up purposes

Preliminary wash yes yes1 can coolers

Final wash no no

Box Washers yes no can coolers

Potential Water Reuse for Selected Food Processing OperationsSource of

Can reserved Can effluent make-upOperation water be used? be used? water

1Use in preceeding operation under precautions.2Use in can coolers if quality is maintained.

Figure 5-5

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Fruit and VegetableProcessingThe fruit and vegetable processing industriesmay be described as consisting of two segments:fresh pack and processing. The former collectscrops and field packs them into lug boxes orbulk bins for shipment to a produce finishingplant. Products are cooled to preserve integrityand fumigated or treated to control insect in-

festation or microbial disease development.Products may be culled, graded or trimmed.Product is sold as fresh produce. The process-ing segment, or packers, includes all unit op-erations, extending the shelf life of food beingprocessed and adding value through producemodification to satisfy market niches.

The fresh pack segment of the industry sharesunit operations with the processing segment.These operations are the sorting/trimming,washing, grading and packing lines. But afterthe packing lines, additional unit operationsmay add to the waste-generating scheme for theprocessing segment alone. Additional opera-tions may include combinations of peeling,stemming, snipping, pitting, trimming, chop-ping and blanching. In some instances, the fi-nal product is dehydrated (e.g., chopped on-ions). In others, it is packaged and processed.Processing can include one treatment or a com-bination of several treatments (e.g., acidifying,brining, freezing, cooking or cooling).

Water and WastewaterUse in the FoodProcessing Industry*The following sections discuss major water-using and waste-generating processes in fruit,vegetable, dairy, meat, poultry and oil process-ing. The information is provided to help foodprocessing managers evaluate water use per-formance and consider additional water effi-ciency measures. In the absence of water usedata, wastewater (hydraulic) loadings informa-tion is presented as a reference for water use.

*Excerpts from “Waste Management and Utilization In FoodProduction and Process,” CAST, October 1995.

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Vegetable products

Asparagus 1.9 8.5 29.0

Bean, snap 1.3 4.2 11.2

Broccoli 4.1 9.2 21.0

Carrot 1.2 3.3 7.1

Cauliflower 12.0 17.0 24.0

Pea 1.9 5.4 14.0

Pickle 1.4 3.5 11.0

Potato, sweet 0.4 2.2 9.7

Potato, white 1.9 3.6 6.6

Spinach 3.2 8.8 23.0

Squash 1.1 6.0 22.0

Tomato, peeled 1.3 2.2 3.7

Tomato, product 1.1 1.6 2.4

Fruit Products

Apple 0.2 2.4 13.0

Apricot 2.5 5.6 14.0

Berry 1.8 3.5 9.1

Cherry 1.2 3.9 14.0

Citrus 0.3 3.0 9.3

Peach 1.4 3.0 6.3

Pear 1.6 3.6 7.7

Pineapple 2.6 2.7 3.8

Pumpkin 0.4 2.9 11.0

Major water use and waste-generation points as-sociated with the fruit and vegetable industry in-clude the washing steps for raw and processedproduce, peeling and pitting practices, blanching,fluming the produce after blanching, sorting andconveying the product within the plant and cool-ing after processing. Reducing size, coring, slic-ing, dicing, pureeing and juicing process steps, as

Wastewater Characterization

Major wastewater characteristics to be consid-ered for the vegetable and fruit processingindustry are the wide ranges of wastewatervolume and the concentrations of organic

well as filling and sanitizing activities after pro-cessing, also contribute to the waste stream.

Representative Wastewater Loadings Per Ton of ProductAssociated with Typical Vegetable and Fruit Raw Products

Flow Flow Flow(1,000 gal/ton) (1,000 gal/ton) (1,000 gal/ton)

Crop minimum mean maximim

Figure 5-6

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materials. Wastewater characteristics can beinfluenced by a number of factors such as thecommodity processed, the process unit opera-tions used, the daily-production performancelevel and the seasonal variation, e.g., growingcondition and crop age at harvest. Figure 5-6presents historical data collected from rawwastewater discharged from the vegetable- andfruit-processing industry.

Water Use and Wastewater Sources

In the processing environment for vegetableand fruit material handling, heating, coolingand packaging, there are six major contribut-ing point sources for waste. These sources arethe following operations: (1) raw producewashing, grading and trimming, (2) washingafter steam/lye peeling and/or size reducing,(3) blanching and fluming, (4) filling, (5) sani-tation/plant cleanup, and (6) processed prod-uct cooling. Plant management practicesgreatly influence process operation efficiencyrelative to final product yield and waste quan-tity generated. (Refer to Figure 5-6 for industrialvariability.)

Water Use and Waste Minimization

Ideally, considerable waste reduction can beachieved if harvesting equipment permits ad-ditional stems, leaves and culled materials toremain in the field during harvest. If cropwashing, grading and trimming can occur inthe field, then additional soil and food resi-dues will remain at the farm. Realistically, mostsuch wastes are being handled at vegetable andfruit processing plant sites. Primary waste-management strategies used by this industryare water conservation and waste-solids sepa-ration.

Water use by the vegetable and fruit process-ing industry is essential to the washing, heat-ing and cooling of food products. But the in-dustry has adopted a number of practices,showing increased sensitivity to the need forwater conservation:

Use of air flotation units to remove sus-pended debris from raw crop materials.Recovery and reuse of process waterthroughout the processing plant.Decrease of water volume use in peel-ing and pitting operations, as well asdecrease of raw product losses.Separation of waste process streams attheir sources, for potential byproductuse.Countercurrent reuse of wash andflume/cooling waters.Separation of low- and high-strengthwastestreams.Installation of low-volume, high-pressurecleanup systems.Conversion from water to steam blanch-ing.Use of air cooling after blanching.

1.

2.

3.

4.

5.

6.

7.

8.

9.

Fruit Processing (Canning,Freezing, Fermenting, etc.)The initial preparation processes for canned,frozen and fermented fruits are washing, sort-ing, trimming, peeling, pitting, cutting or slic-ing, inspecting and grading. Unwanted andundesirable materials must be removed beforethe fruits undergo additional processing, butnot all fruits are subject to each step. For ex-ample, cherries and plums may be cannedwhole and unpeeled, whereas apples, peachesand pears must be peeled and either cored orpitted before being canned. Peeling can be byhand or with machines, chemicals or steam.After inspection and grading, the peeled fruitsare conveyed mechanically or flumed to prod-uct handling equipment for processing.

The converted fruit handling processes are canfilling, syrup adding, exhausting and sealing,thermoprocessing, can cooling and storing.Processing equipment and plant floors usu-ally are cleaned at the end of each shift and soconstitute a final source of waste materials (seeFigure 5-7).

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Water and Wastewater Management

Several water conservation and waste preven-tion techniques are available by which to de-crease water volume. These techniques in-clude:

Figure 5-7

Wastewater Loadings PerTon of Product from

Canned FruitsFlow

Fruit (gallon/ton)

Apple 500,000

Apricot 500,000

Cherry 200,000

Citrus 300,000

Peach 400,000

Pear 400,000

Pineapple 50,000

Other fruit 800,000

The use of high-pressure sprays for clean-up.The elimination of excessive overflowfrom washing and soaking tanks.The substitution of mechanical convey-ors for flumes, the use of automatic shut-off valves on water hoses.The separation of can cooling waterfrom composite waste flow.The recirculation of can cooling water.When can cooling water is not recircu-lated, it may be reused in caustic soda(NaOH) or in water peeling baths, inremoval of NaOH after peeling, in pri-mary wash of the raw material, in can-ning belt lubrication, and in plantcleanup operations.

Dairy ProcessingThe processing of dairy products often entailsvarious unit operations. These generally in-

clude the receiving and the storing of rawmaterials, the processing of raw materials intofinished products, the packing and the stor-ing of finished goods and a number of ancil-lary processes (e.g., heat transferring and clean-ing), associated indirectly with processing anddistributing.

Equipment and facilities for receiving, trans-porting and storing raw materials are muchthe same industrywide. Bulk carriers unloadproducts in receiving areas by means of flex-ible lines or dump material into hoppers con-nected to fixed lines and subsequently trans-ferred by pump to storage. Storage facilitiescan be of the refrigerator, vertical or silo type,with storage tanks containing either liquid ordry products and ranging in volume from afew thousand gallons to one million gallonsor more.

Milk, a perishable product made up of fat,protein, carbohydrates, salts and vitamins, isan ideal food for microorganisms as well asfor humans. Thus, it needs to be protectedfrom contamination, and much of the effortsof the dairy industry are directed to this end.Milk and its byproducts are processed accord-ing to approved procedures, on machinerynormally run no longer than about 20 hoursper day. Much equipment is dismantled daily.Systems may be cleaned in place or after theyare taken apart. Automated cleaning systems,now predominant in the industry, require lesslabor but more water and cleaning chemicalsthan hand washing of dismantled equipment.

Dairy processing wastewaters are generatedduring the pasteurization and the homogeni-zation of fluid milk and the production ofdairy products such as butter, ice cream andcheese. The principal constituents of thesewastewaters are whole and processed milk,whey from cheese production and cleaningcompounds.

Wastewater and Management

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Water use in the dairyproducts industry de-pends on plant complex-ity and water-manage-ment practices. Processwasteloads also differ con-siderably and are influ-enced greatly by the ex-tent to which the plantcontrols raw material and

product losses. Raw wastewater loading for theAmerican dairy industry is summarized by com-modity segment in Figure 5-8.

Milk product losses typically range from 0.5percent in large, technologically advancedplants to greater than 2.5 percent in small,older plants. Given redoubled effort by man-agement, water usage in most plants could bedecreased to approximately 0.50 L/kg milkequivalent processed. Considerable improve-ments in water and waste management remainimportant and realistic industry goals.

Innovations

Summary of American Dairy and MilkProcessing Plant Effluent Loadings

Wastewater Wastewater(kg ww/kg milk) (kg ww/kg milk)

Products range average

Milk 0.10-5.40 3.25

Cheese 1.63-5.70 3.14

Ice cream 0.80-5.60 2.80

Condensed milk 1.00-3.30 2.10

Butter 0.80

Powder 1.50-5.90 3.70

Cottage cheese 0.80-12.40 6.00

Cottage cheese and milk 0.05-7.20 1.84

Cottage cheese, ice cream and milk 1.40-3.90 2.52

Mixed products 0.80-4.60 2.34

Meat and PoultryProcessingThe meat and poultry processing industriesin the United States together make up a $117billion per year industry. The U.S. Depart-ment of Agriculture reported that the valueof red meat production for 2007 totaled $36.1billion. Most red meat processing plants are

In recent years, technological innovations withmembrane systems have provided many newopportunities. For example, ultrafiltrationnow can be used instead of the biological sepa-ration of organic material from liquid sub-strate. And instead of using reverse-osmosissystems for tertiary waste treatment, some foodplants use them to recycle internal liquid wastestreams. The outflow from reverse-osmosistreatment can be of better quality than thenative water.

Figure 5-8

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Beef 150 - 450

Turkey 11 - 23

Broiler 3.5 - 10

Waste and Byproducts

Most waste products are recovered somehowby the industry. Blood, feathers and bone usu-ally are processed into a meal product for ani-mal feed. Similarly, meat scraps unsuitable forprocessing into food products are sold or givento rendering facilities for processing into ani-mal and pet foods. The ultimate characteris-tics of solid materials and wastewaters gener-ated by these source areas in a plant and unre-covered for another use differ greatly and areaffected by:

Animal size and typeProcessing levelConveyance meansProcessing water useCleanup and housekeeping procedures.

1.2.3.4.5.

Water UsageWater use for broiler processing typicallyranges from 3.5 to 10.0 gal/bird; for turkeys,11 to 23 gal/bird. Flow rates of 350 gal/ani-mal have been reported for beef slaughteringplants. In one beef slaughtering operation,water use dropped from 458 to 187 gal/headafter water conservation measures wereadopted. Similar water use numbers appearin the examples in Figure 5-9.

Water is used for chilling, scalding, can retort-ing, washing, cleaning and waste conveying.For example, poultry processing uses approxi-mately 3.5 to 7.0 gallons of water per bird offour-pound average weight. All broiler process-ing plants are required to have a scalder over-flow rate of 0.25 gal/bird and a chiller over-flow rate of 0.50 gal/bird. In many instances,this water is used in the plant for the trans-port of feathers and offal from the processing

Typical Water Consumptionfor Beef, Turkey and Broiler

Processing

WaterAnimal type (gallon/animal)

Figure 5-9

area. One researcher, studying a broiler pro-cessing plant, reported that processing ac-counted for 76 percent of the water use, with13 percent used in cleanup and 12 percentused in downtime.

Beef processing water usage, primarily fromcarcass washing and process clean-up, has beenreported in the range of 150 to 450 gallonsper animal processed. As a general rule, meatprocessors use about one gallon of water perpound of processed hamburger meat.

Use and Minimization of WastesThe amount of wastewater generated by theindustries can be decreased largely throughchanges in cleanup practices. Water use canbe minimized by means of commercially avail-able high-pressure, restricted flow hoses, whichcan be fit with automatic shutoffs to preventwater loss during inactivity. Many materialscan be handled mechanically. For example,flour and other dry material can be vacuumedfrom the floor, and augers and conveyors canbe used to transport scrap meat and viscera.

Chiller and scalder water is reused in mostpoultry processing plants for flushing waterto remove offal and feathers. Reconditioningof chiller overflow through the use of filtra-tion and ultraviolet irradiation has been rec-ommended. Limits to use include the poten-tial of bacterial contamination by coliforms

located in the Midwest; most poultry process-ing plants are in the Southeast and the Mid-Atlantic. Processing of prepared meats, includ-ing canned cooked products, luncheon meats,hot dogs, bacons, stews and other ready-to-eatmeat products, has expanded rapidly in recentyears.

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Grain Processing for OilsThe extracting, refining and processing ofedible oils produces a variety of waste prod-ucts. This chapter, which focuses on conven-tional caustic refinements and on relateddownstream processes, briefly reviews majorprocesses and facilities, especially as they re-late to waste generation and control.

Fats and Oils Processes andWastewater Loads

from a Well-run FacilityFlow

Process (gallons/day1, avg.)

Milling and extraction 75,000

Caustic refining 11,000

Further processing 5,000

Deodorizing 5,000

Acidulating 19,000

Tank car washing 5,000

Packaging 10,000

Subtotal 130,000

Margarine 70,000

Salad dressing/mayonnaise 50,000

TOTAL 250,000

1gallons/day = gallons per dayns/day1, avg.)

Process Components and MajorWastewater SourcesFigure 5-10 lists primary processes and associ-ated wastewater loadings from a well-run fatand oil processing facility. Separate totals arepresented with and without salad dressing andmayonnaise because these processes often areabsent in a facility. Certain oil processing andrefining operations have no oil seed process-ing facilities, but instead bring in crude veg-etable oil. To account for this prac-tice, adjustments can be made tothe figures in the table. Data pre-sented in Figure 5-10 are based onthese operating parameters:

Milling and extracting:80,000 bushels per day.Caustic refining with single-stage water wash: 60,000 lb/hr,nondegummed soybean oil.Semicontinual deodorizingwith scrub cooler, baromet-ric condenser with atmo-spheric cooling tower.Acidulating of soapstock andwashwater with 90 to 95 per-cent recovery efficiency.Bottling line and/or other ex-tensive liquid-oil packaging.Margarine, mayonnaise andsalad dressing productionand packaging.

1.

2.

3.

4.

5.

6.

Obviously, operations of an atypical size orthose omitting certain processes will have dif-ferent waste loads. This applies especially to op-erations involved in acidulation or in mayon-naise and salad dressing processing. The effectsof process control and its impacts on wastewa-ter loading are very important. As noted, theseloadings are representative for an operation run-ning reasonably well from a process loss con-trol standpoint. But actual loadings depend onhow well plants are run.

A final source of wastewater is contaminatedrunoff from truck and rail loadout areas andfrom tank farm drainage. During rainy peri-ods, runoff from these sources can contrib-ute the equivalent of five to 10 gal/minute tototal daily average flow and, in fact, may af-fect peak flows to a much greater extent.

Figure 5-10

or by Escherichia coli. Recycling is limited bythe characteristics of the wastestream and bythe potential for contamination of food prod-ucts.

7. Washing of tank cars for finished oilonly (cars carrying crude oil excluded).

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M E T A L F I N I S H I N G

AlkalineCleaner Rinse Acid "pickle"

Surface prep Rinse ElectroplatingProcess Rinse

Work Flow

Rinse water feedRinse water feedRinse water feed

During the past 15 years, the metal finishingindustry has made great strides in reducingwater use. In a 1994 survey by the NationalAssociation of Metal Finishers, 68 percent ofrespondents had made substantial reductionsin water use through pollution preventiontechniques. On average, these shops had re-duced water flow by 30 percent or about20,000 gpd. Even with these achievements,metal finishing businesses still continue tohave significant opportunities to further re-duce water use. Water efficiency within an in-tegrated pollution prevention program canprovide these advantages for metal finishers:

Lower operation cost by reducing waterbill.Reducing wastewater treatment costs.Potentially improving pollutant removalefficiency in wastewater treatment.

Improving rinsing efficiency represents thegreatest water reduction option for metal fin-ishers. A rinsing efficiency program also is thefirst step to enable metal finishers to imple-ment progressive pollution prevention tech-niques, such as chemical recovery from themore concentrated waste stream and the po-tential of closed-looping the electroplatingprocess.

Improving Rinse WaterEfficiencyIn the metal finishing industry, rinsing qual-ity has a dramatic effect on product quality.Improvements in rinsing efficiency must becarefully integrated into quality control and

Reducing or delaying need for treatmentcapacity expansion.

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assurance programs. Rinsing efficiency im-provement techniques for metal finishers in-clude improved rinse tank design, flow con-trol techniques and alternate rinse tank con-figurations (see Figure 5-11).

Rinse Tank DesignProper design of rinse tanks will improve rins-ing efficiency and reduce water use. Optimumrinse tank designs provide fast removal ofchemical solutions or “drag-out” from theparts. These techniques can enhance rinsetank design:

Survey Rinse Water Efficiency ApplicationsPercent of business Success

Technique using technique1 rating2

Flow restrictors 70 4.1Countercurrent rinse 68 4.2Manually turn off rinse water when not in use 66 3.6Air agitated rinse tanks 58 3.7Spray rinses 39 3.8Reactive or cascade rinsing 24 3.8Conductivity controllers 16 3.3Flow meter or accumulator 12 3.7Timer rinse controls 11 3.25

1Based on NCMS/NAMF study in 1994--318 metal finishers responding.2Success rating based on scale of one to five, with five bing the highest

Figure 5-11

Provide agitation to the tank by air blow-ers (not compressed air), mechanicalmixing or pumping/filtration systems.Prevent feed water short-circuiting byproperly placing inlets and outlets onopposite ends of the tank.Use inlet flow baffle, diffusers, distribu-tors or spray heads.Select the minimum sized tank appro-priate for all parts/products.Consider spray rinsing instead of immer-sion for flat-surfaced parts.Consider ultrasonic rinsing applicationswhere applicable.

Flow Control Techniques

The use of flow restrictors is a very effectivemeans to ensure excessive water is not fed tothe process line. Flow restrictors are installedin the feed line of a tank. They are commonlyelastomer washers with an orifice that issqueezed smaller with increasing line pressure.They are available in rates ranging from 0.1gpm to greater than 10 gpm. The flow rate ofa restrictor should be chosen to provide suffi-cient water for quality rinsing. Restrictors workbest in consistent production applications.

Flow Restrictors

Flow Cut-off Valves(Manual and Automatic)Water flow to rinse tanks should be shut offwhen the process lines are not in use. Thiscan be done manually or automatically. A foot-actuated feed valve can be used in job shopsthat have discontinuous processing demands.The rinse water valves can be activated onlywhen components are being rinsed. For largercontinuous operations, solenoid valves canturn off rinse water lines when power to theelectroplating line is turned off. For automatic

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conveyorized lines, photosensors also canbe used to turn on water valves or sprayheads only when parts are passing thatrinse stage.

Acceptable Rinse WaterContaminant Limits

Conductivityin micromhos

Rinse bath for (μmho)

Alkaline cleaner 1,700Hydrochloric acid 5,000Sulfuric acid 4,000Tin acid 500Tin alkaline 70-340Gold cyanide 260-1,300Nickel acid 640Zinc acid 630Zinc cyanide 280-1,390Chromic acid 450-2,250

Figure 5-12

Conductivity Meters and Controllers

The most accurate way to control rinsewater flows and purity can be achievedusing conductivity controls. The use ofconductivity meters and control valves willsubstantially reduce rinse water flow andensure a set water purity standard is al-ways being met in the tank. Electrical con-ductivity increases as the concentration ofcontaminant ions increases.

Conductivity meters indicate the concen-tration of contaminant ions in the rinsewater in units of micromhos (μmhos), alsoreferred to as microsiemens. Specific con-ductance can be roughly correlated to to-tal dissolved solids in mg/L using empiri-cal data.

Many metal finishing facilities have installedconductivity controllers on the rinse tanks thattrigger the introduction of fresh water onlywhen the conductivity reaches a certain setpoint. This practice significantly reduces wa-ter consumption, typically by 40 percent.

Conductivity rinse water flow controllers aremost useful on discontinuous electroplatingoperations. The cost of installing each rinsewater conductivity controller will be between$1,000 and $2,000 and typically will have aneconomic payback of about one year. In thepast, conductivity controllers required highmaintenance to prevent fouling of electrodes.Newer inductive loop or electrodeless sensorsare less susceptible to fouling than conven-tional electrode types. Determining the opti-mum set point for these controllers also isimperative to conserve water and maintainquality. Figure 5-12 can be used as a startingpoint for determining acceptable rinse waterpurity standards.

CASE STUDY

Conductivity Controller

Artistic Planting and Metal Finishing inAnaheim, Calif., installed electrodelessconductivity controllers on nine rins-ing tank systems. Artistic Plating is sav-ing 55,000 gallons per week, whichequates to a 43 percent rinse watersavings. The conductivity system re-sulted in decreased rinse water use,wastewater generation, wastewatertreatment chemical use and sludgegeneration. Artistic Plating experi-enced no adverse quality effects usingthe controller. Total system paybackwas one year.

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Portable conductivity meters also can be usedto establish a fixed flow rate to maintain anappropriate rinse water quality. Once rinsewater purity levels are established, permanentflow restrictor valves can be installed in thewater supply line to the individual rinse tanks.This technique is suggested only where elec-troplating production is consistent. Again, useFigure 5-12 as a starting point.

Flow MetersRelatively inexpensive meters or accumulatorscan be installed on the main water feed line,process line or on individual rinse tanks.While meters and accumulators do not actu-ally save water, they do allow for careful moni-toring of usage and can identify optimumwater utilization (or excessive waste), leaks andsystem failures.

CASE STUDY

Rinsing Efficiency

C & R Hard Chrome & ElectrolysisNickel Service Inc. in Gastonia recon-structed its electrolysis nickel line toincorporate several pollution preven-tion techniques and improve process-ing efficiency. Single-rinse tanks wereswitched to a system of multiplecounterflow rinse tanks to reducewater consumption. Restrictive flownozzles on water inlets were addedto better control and reduce waterconsumption. The process line up-grades reduced water consumption by87 percent, from 7,500 gallons to lessthan 1,000 gallons per day.

Alternative RinsingConfigurations

Countercurrent rinsing is the practice of over-flowing rinse water between a series of rinsetanks so that the water flow is in the oppositedirection to work flow. This results in the fi-nal rinse being the cleanest. Countercurrentrinsing significantly reduces water usage with-out sacrificing rinsing efficiency. A commonconfiguration for a countercurrent rinse is twoto three rinse tanks in series. Water consump-tion can be reduced more than 90 percent justby adding a second counterflowing rinse to asingle rinse tank. (See Figure 5-13.)

If floor space is a problem, a partition couldbe installed in the existing rinse tank with ametal divider acting as a weir. This modifica-tion can be made only if there is sufficientroom for the parts rack or barrel in the tank.

Countercurrent Rinsing

Reactive Rinses and Reuse

A reactive rinsing system involves diverting theoverflow from an acid rinse to an alkaline rinsetank. (See Figure 5-14.) The acid ions neutral-ize the alkaline ions without causing contami-nation of the rinse water or compromisingplating quality. By reusing acid rinse baths foralkaline cleaner rinses, the effectiveness of thealkaline cleaner rinses can be improved whilereducing water consumption by 50 percent.Furthermore, the rinse water from single rinsestages following plating baths has been shownto effectively clean products in rinses follow-ing acid or alkaline cleaning without affect-ing the rinse effectiveness. Rinse water some-times can be reused from a critical rinse to aless critical rinse in the same processing lineor between processing lines. Care should al-ways be taken to ensure cross contaminationis not problematic.

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Figure 5-13

Spray Rinsing

Spray rinsing can be incorporated into existingmetal finishing process lines to further reducewater use. Typically, spray rinses can be useddirectly over heated process tanks or over a deadrinse to reduce drag-out. By spraying drag-outback into its process tank or into a concentratedholding tank, less water will be needed for finalrinsing.

Spray nozzles for these applications typically haveflow rates ranging from .04 to 1.0 gpm. Nozzlescan be hydraulic nozzles, which spray water only,or air-atomized nozzles, which use compressedair. Nozzle spray patterns are available in fullcone, hollow cone, flat fan and finer misting andfogging types. Spray angle and length of spray

pattern is important when specifying the num-ber and spacing of nozzles. Components of spraysystems include a water supply, filter, switch,check valve and nozzle(s). The approximate in-stalled cost for a spray system over an existingtank is less than $2,000. Case studies have shownthese systems are paid for in less than one yearin water and chemical savings.

Reducing Drag-Out toImprove RinsingThe term “drag-out” refers the residual solu-tion that still is adhering to a part when itleaves a process bath. The drag-out is the solu-tion that must be rinsed off the part. By em-ploying techniques that reduce the volume of

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drag-out, metal finishers can rinse parts usingless water. Potential drag-out reduction tech-niques for metal finishers include:

Figure 5-14

AlkalineCleaner Rinse Acid "pickle"

Surface prep Rinse ElectroplatingProcess Rinse

Work Flow

Rinse water feed

Rinse Water Reuse and Reactive Rinsing

Operating bath formulations at mini-mum chemical concentrations.Maximizing bath operating temperatureto lower bath viscosity.Using wetting agents to reduce surfacetension. Up to a 50 percent drag-outreduction can be achieved.Racking parts to maximize drainage.Drag-out rates for very poorly drainedparts are three to 12 times the rates forwell-drained parts with vertical, horizon-tal and cup-shaped surfaces.Extending drainage time over processtank or dead rinse tank.Increasing drip time from three to 10seconds reduces the drag-out remainingon a part by an average of 40 percent.Using spray or fog rinsing over the pro-cess tank or dead rinse tankPositioning drainage boards between theprocess tank and next rinse tank.

By reducing the volume of process solutionscarried out of the plating tank, metal finish-ers can reduce rinse water, conserve expen-sive bath formulations and directly reduce thepollutant mass loading to wastewater.

Wastewater ReuseTechniquesSome electroplating shops are reusing treatedwastewater for non-critical rinsing steps such asafter alkaline cleaners and acid pickling steps.The reuse of conventionally treated wastewater(via hydroxide precipitation) should be cautioneddue to the introduction of high dissolved solidsinto the plating line. Drag-out and drag-in fromconventionally treated water can contaminateother process baths with contaminants such assodium. In conjunction with advanced mem-brane separation techniques such as reverse os-mosis, wastewater reuse becomes more feasiblefrom an operations standpoint. Some compa-nies have successfully closed-looped electroplat-ing rinse tanks by employing continual cationicand anionic exchange reclamation of metals.

An electro-coagulation/ultraviolet process pat-ented by Pasco Inc., has been successfully ap-plied to treat and reuse alkaline and acid rinsewaters and bath dumps. The process offers costeffective high quality water reuse and low sludgegeneration due to no needed chemical additionsfor solids coagulation and flocculation treatmentstages.

Other novel applications of wastewater treatmenttechniques such as electro-coagulation and ab-sorptive/adsorptive media hold promise to en-able electroplaters to close loop their operations.

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A facility water audit or survey is the key start-ing point of any water efficiency program.This chapter provides supplemental informa-tion and tools for the water audit team con-ducting the plant survey (see Chapter 3).

Water Audit PreparationThorough preparation for the water audit willensure maximum results and efficiency. Topmanagement should be completely support-ive of this effort. Collect the following infor-mation regarding the facility’s water use, iden-tify all personnel familiar with the operationand record information collected on the wa-ter survey data sheets (see Data Sheet at end ofthis chapter):

The exact location of the facility in-cluded in the audit.The age and physical size of the facili-ties, including the number of buildingsand floor space (in square feet) for each.Plumbing drawings, riser diagrams andirrigation plans.Names, phone numbers and e-mails offacility contacts.Specific services or products producedat the site:

The operatingschedule of the fa-cility, number ofemployees pershift, mainte-nance shifts andother operating information.A water use profile (graph) showing thetotal water use and water used per unitof product per month for the last threeyears (one year minimum).Copies of the proposed billing rates forenergy, water and wastewater for thenext two years (if known).List of all water-using equipment, includ-ing the manufacturer’s recommendedflow requirements.Inventories of sanitary fixtures and anywater-saving features.

Record the number of mealsserved, number of guest rooms andoccupancy data for service estab-

lishments, such as restaurants, ho-tels, hospitals, military bases andschools.For manufacturing sites, identifythe amount of water used per quan-tity of product produced (that is,gallons per ton of product or gal-lons per gross of widgets).For schools and other such institu-tions, calculate and record theamount of water used per personper day.

6.

7.

8.

9.

10.

6 AuditingMethodologyand Tools

1.

2.

3.

4.

5.

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Outdoor water use and irrigation con-trols.Previous water and energy surveys.All water delivery records from watermeters, tank trucks or the facilities’ ownwells. Accurate water meters are essen-tial for a valid water audit. Source watermeters indicate the amount of watersupplied to the site. Sub-meters indicatewater used for specific processes andindividual buildings on the site. Obtainthe following meter information beforestarting the audit:

11.

12.13.

Any calibration test results for metersto adjust past meter readings to reflectactual water use.

14.

If the firm has never performed a significantwater efficiency study, experienced help maybe needed. Experienced assistants may beavailable from the following:

Other units within the organiza-tion.Local, state or university technicalassistance services.Consultants who understand theprocesses.Water, gas, energy and electric utili-ties.

Submetering is an excellent way to accurately account for large water uses in spe-cific processing equipment for departments within the plant. Submetering helpspersonnel become familiar with water use for all operations and indicates whetherequipment is using water when it is not needed. (In some rinses, water is leftrunning continuously, even when the need is only occasional.)

To obtain the appropriate size for a submeter, use the actual flow rate rather thanjust pipe size. Use temporary strap-on meters to determine the approximate flow.Then, the correct size of the positive displacement meter can be determined be-fore installation. Temporary meters also will indicate whether it will be cost-effec-tive to install permanent meters.

Bucket and stopwatch is a simple and accurate measurement tool. To use this method,collect a specified amount of process water for a specific time period (e.g., onequart per minute, which is equivalent to 0.25 gpm).

Micro-weirs are small hand-held weirs that are used to measure low flows of water(0.5 to six gpm) in tight spaces, such as under lavatory faucets.

Measuring In-Plant Water Usage

Gather necessary tools needed for theaudit: camera, bucket, stopwatch, etc.

15.

Location of all water supply metersthat record deliveries from utilities,wells and other water sources.Location of all on-site process andbuilding meters.Sizes of all meters.

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Conducting the WaterAuditThe next step is to conduct a walk-throughsurvey with facility personnel who are knowl-edgeable of how water is used in each area ofthe facility. Use direct observation and mea-surements. Identify and record all pieces ofequipment that use water. Check with equip-ment operators who may have important first-hand information. Record information onwater survey data sheets (see pp. 112-116) Usethe following procedure to conduct the step-by-step survey:

During the walk-through, record hoursof operation for each piece of equip-ment, including domestic and kitchenoperations. Identify water piping lay-outs, particularly in areas of older equip-ment, to aid with identifying water uses.Note those pieces of equipment thathave multiple uses of water (e.g., water-cooled ice machines).Identify water f low and quality asneeded for each use. This informationmay be needed to determine if dis-charges from one use can be re-used asa potential supply for a different appli-cation. Include these parameters:

1.

2.

Temperature.Water quality indicator parameters,such as pH, total dissolved solidsand conductivity.Other key water quality parameterssuch as biochemical oxygen de-mand, chemical oxygen demand,metals, or oil and grease.

Where possible, measure the actualamount of water being used. The mostdirect way to measure flow rates is witha bucket and a stopwatch (see Figure 6-1,p. 110). Consider installing meters onmajor water-using processes or plant de-partments to record the quantity ofwater used.Check water quantity and quality ofwater specified within the equipment

3.

4.

operating manuals. Equipment issometimes operated at higher flowsthan required by the manufacturer’sspecifications. Ask qualified engineersto review the specifications and adjustflows accordingly. Further, investigatewhether the processes can still oper-ate properly with further reductionsin water flow. Be sure to record flowrates before and after changes aremade to evaluate the effects of reducedflow.Read water meters regularly and com-pare actual water use to the facility’swater reduction goal. After determin-ing daily use rates, the frequency ofthe readings should be adjusted to beconsistent with the volume of waterused, the cost of reading the meters,and potential excessive use fees. Forexample, large water users (more than50,000 gpd) should continue to readmeters daily. Commercial businessesusing water for sanitary purposes onlymight read meters biweekly ormonthly.Identify flow and quality of wastewa-ter resulting from each use.Include any internally generated flu-ids in the water audit. Water may begenerated as a byproduct of process-ing raw materials, such as fruits orfrom oil/water separation equipment.Determine the quantity and quality ofthese fluids and whether there arepotential on-site uses for these fluids,such as housekeeping or cooling.

5.

6.

7.

Use survey results to prepare a water balancediagram (see Figure 3-1, Chapter 3) to depictall water uses from source through on-site pro-cesses, machines and buildings, and finally,to evaporation and discharge as wastewater.If unaccounted for water is greater than 10percent, revisit the major areas of water use,talk further with plant operators, or take ad-ditional measurements.

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Water Audit ReportProper and efficient presentation of the wa-ter audit findings and recommendations isimperative for facility decision-makers. Thewater audit report should contain the follow-ing elements:

Executive summary of the recommen-dations, quantifying of savings, invest-ment costs and payback periods.Introduction.Facility description.Water use history for one or more years.Water use balance.Which efficiency option, technical dis-cussions and savings calculations.

1.

2.3.4.5.6.

Additional WaterAuditing Tips

Measuring tools should be used after thewalk-through with facilities staff or theaudit team. There is no time to startmeasuring flows while the assessors arebeing shown the facility.The quality of the audit depends onaccurate information for the facilitiesmanager or staff guiding the walk-through. Always try to speak directly toline operators or staff working in thewater-consuming operations to confirminformation.For external auditors, follow-up trips arealmost a necessity when water balancecalculations to estimating water use bycategory do not align with meter con-sumption records.Spikes on yearly water consumptiongraphs are a reminder to the auditor tofind out the whole story of the wateruse history.While accounting for water use at largecommercial and industrial facilities, itmay be difficult to keep “unaccountedfor” less than 10 percent. A range of sixto 12 percent unaccounted for water iscertainly acceptable.

Energy savings if applicable.Data normalization for follow-up withsuggested time frame.

7.8.

Leak DetectionAll facilities will experience some leaks. Leaksmay range from a fraction of a percent up toseveral percent of total water use. Telltale signsof a leak include low water pressure or dirty wa-ter, or both, as well as an unusually high volumeof unaccounted for water. Common locationsfor leaks are in piping joints, restroom fixtures,pump seals, loose nozzles/shut-off valves, drink-ing fountains, processing equipment and otherlocations. Eliminating such leaks typically in-cludes tightening or replacing fittings.

Leaks can be identified by visual or audio ob-servations. Water fixtures and process equip-ment should be observed both during use andduring down time. All employees should beresponsible for notifying maintenance per-sonnel of leaks, and maintenance personnelshould make leak repair a priority.

Water Leak Equations

Rates of water loss for a roughlycircular hole can be estimated usingthe Greely equation (see Figure 6-2):

Q = (30.394)(A)(square root of P)Where Q is leak rate in gpm, A is thecross-sectional area of the leak insquare inches, and P is the line pres-sure in pounds per square inch.

Leaks in joints or cracks can beestimated by this equation:

Q = (22.796)(A)(square root of P)Where Q is leak rate in gpm, A is thearea of the leak in square inches, andP is the line pressure in psi. Forexample, a 1/32” wide crack, 1” longwill use 4.5 gpm at 40 psi.

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Determining Water Lossby LeaksDetermining the volume of water loss by leaksis important to calculate both water and costsavings by repairing the leak. One of the sim-plest methods to determine leak loss is thebucket and stopwatch method. A small dripalso can be measured by the bucket and stop-watch method. Mathematical estimates ofleaks can also be used.

AWWA: Waterwiser 2008

FIGURE 6-1

1 8.64

2 17.3

3 25.9

4 34.6

5 43.2

Five drips per second is a steady stream.

Drips/Second toGPM Conversion

No. drips Gallons perper second day

FIGURE 6-2

Leak Losses for Circular Holes

0

0.5

1

1.5

2

2.5

0.01 0.025 0.05 0.075 0.1

Diameter of Hole (in)

gpm

20 (psi)40 (psi)60 (psi)80 (psi)100 (psi)

Underground or under-the-floor leaks can bedetected through a leak-detection survey usingthe facility’s water meter. To do so, all water-consuming items inside and outside the build-ing must be turned off. Alternatively, performthe survey after the last shift has left and nowater is being used in the facility; then observethe water meter for a minute or more. If themeter dial moves continually during this time,a leak is indicated. Another method is to recordthe numbers on the meter and come back anhour later to check the reading, making surethat no water is used during this time. If themeter reading has increased, there is a leak.

If an underground leak is suspected or detectedusing the water meter, but the leak’s location isnot readily identified, it may be necessary tohave a leak detection survey performed by aservice firm. Such firms use state-of the-art au-dio sound systems to pinpoint the leak’s loca-tion. To identify a leak or problem area, a por-table listening device allows the user to verifythat a leak is present in a general area. The equip-ment consists of (1) a base unit that containsbatteries and electronic components that am-plify leak noise and filter extraneous noise, and,(2) an acoustic sensor that attaches to the roadsurface or pipe itself, as well as a pair of head-phones. The cost of this equipment can rangefrom $1,000 to $5,000.

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Positive 5/8 - 2 inches Commercial, medium hotels, apartmentdisplacement complexes and industrial plantsClass II turbine 2 - 6 inches Medium/large hotels, large apartment

complexes to large manufacturing andprocessing plants

Class I turbine 8 - 12 inches Industrial, manufacturing, processing,pump discharges

Compound, high 2 - 4 inches Special high and low demandvelocity styles applications for schools, public

buildings and hospitals

Water Meter IssuesThe size and accuracy of a facility’s watermeter is important when accurately account-ing for water use. Typical types of meters usedfor commercial and industrial settings includepositive displacement, turbine and com-pound meters. Figure 6-3 shows typical ap-plications for meter types and sizes. Watermeters can become less accurate when theintended water use of a facility has changedor when substantial water conservation ac-tivities have been implemented. Water metersshould be of adequate size but not oversized.If a meter is oversized for the facility’s needs,

FIGURE 6-3

Types of Meters and ApplicationsType Common sizes Typical applications

the facility could be paying unwarranted ser-vice charges for the oversized meter. Properlyselected and sized water meters can becomeinaccurate due to wear, which is affected byage and water quality. In-place field testingusing a pitotmeter for large meters and a por-table meter test unit for smaller water meterscan be conducted. In most cases, water usedfor landscaping, cooling towers, etc., that isnot discharged to the sewer can qualify for arebate from the sewer district. However, thevolume of water not going to the sewer mustbe accurately measured by a separate meteror other device to qualify for the rebate.

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Water Survey Data Sheet

This data collection sheet is designed to assist auditors during assessments. Some items maynot be applicable for all assessment situations or conditions.

Assessment Information

Background Information About Water Use

Average water use/bill (for previous year)

Average water use/bill (for year before last)

Size and location of meter(s)

Primary water source

Secondary water source

Potential to reduce meter size? Savings

Should credit be obtained for water that does not go to the sewer? (cooling towers,landscaping)

Is an additional meter required to monitor water not being sewered?

Company name Date of assessment

Address

Phone/FAX Lead assessor

Company contact person/title

E-mail address

Assessment team members

Assessment objectives (special concerns)

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Company Background Data

Number of employees Shifts per day Operating days/week

Size of and type of plant (sq. ft.) Year built/renovated

Business type (manufacturing, college, office, etc.)

If manufacturing, list products and annual production rate

If service or institutional sector, list clients, occupancy rates, meals served per year, etc.

Other pertinent facility data

Current and past water efficiency program measures (policies, training, awareness and goals)

Water Balance and CostsGallons per Percent of Water Cost Sewer Energy/Other

Source of water use Year (est.) Total ($/yr) Cost ($/yr) Costs ($yr)Domestic

Heating/cooling

Rinsing/cleaning

Landscaping

Unaccounted for

Total

System ParametersNumber, types and sizes of buildings at complexGrounds (approximate size in acres) Garages/motor pool/support

buildings (approx. sq. ft.)

On-site water treatment description, rate and costs

Wastewater treatment description, rates and operating costs

Notes

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Water Used in Manufacturing ProcessesVolume used directly in product, per year

Description of water used in processing

Volume used in production (i.e., plating)

Notes

Washing, Rinsing and SanitationVolume used in cleaning, rinsing and sanitation

Description of washing and sanitation processes

Number of mop sinks, etc.

Have improved rinsing techniques (such as counter-current systems, conductivity flowcontrols, improved spray nozzle/pressure rinsing, etc.) been considered?

Are “dry clean-up” practices used instead of hosing down and first-pass pre-cleaningconducted with squeegees, brushes or brooms?

Is water cut off when not in use by flow timers, limit switches or manually?

Notes

Cooling and HeatingDescription of cooling tower evaporative coolers (rated tonnage, types and uses)

Water rate used in cooling towers and equipment

Is condensate being reused?

Description of once-through cooling requirements

Volume used in once-through cooling (air conditioners, air compressors, vacuum pumps,rectifiers, hydraulic equipment, degreasers, etc.)

Or has once-through cooling water for these uses been eliminated through use of chill-ers, cooling towers or air-cooled equipment?

Has blow-down bleed-off control on boilers and cooling towers been optimized?

Notes

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Domestic UseToilets (number, type and tank volume)

Urinals (number and volume)

Lavatory sinks (number and estimated flow)

Showers (number and estimated flow)

Are code-conforming commodes (1.6 gpf), faucet aerators (0.5-1.0 gpm) and low-flowshowerheads (2.5 gpm) in use?

Notes

Landscaping/Outdoor UseLandscape irrigation (estimated gallons per unit of time)

Acreage/square footage landscaped and description

Watering/irrigation system techniques and schedule

Are low-flow sprinklers, trickle-drip irrigation, optimized watering schedules and waterplacement, preventive maintenance and xeriscaping techniques in place?

Notes

Kitchen/CanteenDishwasher(s) description, use and volume

Kitchen faucet/pre-rinse sprayers [number and flow rate (gpm)]

Icemakers, air-or water-cooled and water usage

Garbage disposals in use?

Are “electric eye” sensors for conveyor dishwashers installed?

Have new and water- and energy-efficient dishwashers been considered for futurepurchse?

Notes

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Other Uses, Leaks and Unaccounted-for WaterList any quantifiable leaks and estimated rates

Any other miscellaneous uses of water (car washes, wet scrubbers, ornamental ponds,dust control, etc.)

Notes

Additional NeedsFactors that couuld affect, increase or decrease water use

Any other major opportunities and assessment opportunities revealed, includingEnergy efficiencyLightingHeat recoverySolid waste reductionPollution prevention

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Large commercial, institutional and industrialfacility managers should consider the needto develop a drought contingency plan. Afacility’s drought contingency plan will in-clude many of the water efficiency strategiescovered in this manual, but should also makepreparation for the mandatory water use re-strictions and the possibility of emergencyactions during a severe water shortage.

Facility Plan ApproachThe approach to develop a drought contin-gency plan can be similar to, or piggy-backon, the “Steps of a Successful Water Effi-ciency Program” covered in Chapter 3, butwith a more succinct focus on responding toa water shortage through a number of short-term measures. With top-down support, keymanagement personnel should outline a planwith the participation of key staff in affecteddepartments. Responsibilities for the plan’saction items should be clearly delineated,with special emphasis on emergency response

measures. The plan action steps should beintegrated with the level of water shortageseverity defined by the local water supplier.Predictive timing and internal triggers shouldbe established.

Knowing the local water supply drought re-quirements is an essential early step (see “Un-derstand Your Water Supplier’s Water ShortagePlan,” p. 120). A facility should inventory andunderstand its own water uses and catego-rize these as “non-essential,” “important” and“essential.” Other regulatory rules and re-quirements that may apply to a facility’s di-rect water withdrawal from rivers, reservoirsor diminishing capacity of groundwater wellsshould be reviewed. Daily water use trackingand supply tracking becomes necessary un-der mandatory restrictions and essential un-der emergency levels. As with any contingencyplan, proper communications and employeeinvolvement are essential to managing severedrought impacts.

7 DroughtContingencyPlanning forFacilities Managers

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Facility Plan KeyElementsCommunications

The most successful facility efforts to addressdrought come through timely and continualcommunications with all employees.Whether this is communicated throughdrought updates posted on a manufacturer’sbreak-room tables or special awareness signshanging around the showerheads at a YMCA,the importance of these communicationscannot be overemphasized. Allemployees want to feel like partof the team and that their orga-nization is doing its part tominimize water uses duringtimes of drought.

As larger water users come un-der high scrutiny by communitymembers during a drought, a fa-cility spokesperson should beable to effectively communicatewhat measures and strategies the organizationis taking either in response or proactively.Communicating water conservation successesis an important and positive news release item.

Demand Reductions

Addressing an action plan of key demandresponse measures will likely be the mostimportant and engaging activity of the plan.Tracking water use and related reductionmeasures is the first step. For many commer-cial and institutional facilities, the trackingof water use may not have been conductedin the past. Since water supplier bills may bemonthly, bi-monthly or even quarterly, facil-ity staff will need to read the facility's watermeters on a more periodic basis.

Developing a list of viable drought responsewater conservation measures will require cre-ative input from several representatives in theorganization. Creating an inventory of all

water-consuming equipment and practicesshould be done by a water conservation team.This can be accomplished with a quick wateraudit conducted by team members. (See the“Self-Assessment Checklist” in Chapter 2 for moreresources.) As a list of water conservation ac-tion items is generated, the speed and prior-ity of implementation should be carefully con-sidered. Short-term vs. permanent measuresneed to be noted and managed accordingly.This is also the time to maximize the effectof behavioral water conservation measuresthroughout the facility.

Water Supply Extensions

Larger water-using facilities mayhave their own water supplies todeliver process, cooling or irriga-tion water. Some facilities have con-sidered increasing storage capacityof existing reservoirs and cisterns,some of which are used forstormwater collection. Other facili-ties have drilled wells for new ca-pacity or expanded capacity. The

potential exists for greater water reuse andrecycling from on-site processes or fromtreated public or private wastewater systems.Advance planning is essential for all supplyextension efforts. Some projects have hadrelated environmental permits expeditedduring periods of water use restrictions.

Emergency MeasuresFacility management staff should plan forscenarios of severely restricted water supply -down to having no potable water for domes-tic use at the facility. Could the organizationstill function with other sources of water forproduction needs? Can portable restroomsbe employed and bottled water be distributedto employees? What minimum sanitation andhand-washing requirements need to be ad-dressed? Identifying appropriate vendors, ser-vice providers and governmental officials inadvance is sound planning.

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Businesses and manufacturing facilities inNorth Carolina have employed the follow-ing actions during emergency response todrought conditions:

Shutting down of all restrooms, foodpreparation areas and water fountains.Putting portable restroom facilities inuse.Making bottled water available to em-ployees.Drilling wells to supply water for manu-facturing processes.Bringing in water by tanker truck fromgeographical areas with more abundantwater supplies.Treating and recycling wastewater gen-erated by the manufacturing process andrecycling it back into the manufactur-ing process and/or cooling towers wherepossible.

Drought Response vs. Ongoing WaterEfficiency MeasuresDrought response planning includes manystrategies to meet voluntary, mandatory andeven emergency drought mandates thatwould not normally be employed on a per-manent, year-round basis. Selected examplescollected from North Carolina communitieshave included:

A food processing plant changed itsoperating shift schedule in order to re-duce the number of end-of-shift clean-ups.A business took its water fountains outof service and used bottled water.Facility managers increased the numberof concentration cycles on cooling tow-ers and boilers during drought periods.A canteen service is using paper platesto avoid use of the dishwasher.Reusable water from various sources isbeing accumulated in buckets to flushtoilets.Water used for checking hot water heat-ers is being reused for cleaning jobs.

Condensate from dehumidifiers and airhandlers is being used to irrigate plants.Solenoid valves and flow restrictors in-stalled to shut off/reduce water flowsduring less critical steps of a continu-ous dyeing operations.Sanitizing hand gel used as a substituteto clean hands to enable turning offwater at bathroom sinks.Eliminated once-through cooling ofpumps, compressors, autoclaves andother equipment by placing equipmenton chilled water/cooling tower loops.Individuals expected to cut down ontime in showers and to turn off waterwhen not required for soaping or rins-ing.Members of the hospitality industry areposting drought notices from the mayorthroughout their facilities to encourageguests to be more efficient in the use ofwater.Porta-toilets used in recreational parksto cut down on the use of water-con-suming facilities.Manufacturers captured water fromchiller units and used it for cleaning pur-poses and make-up in a closed loopmachine coolant system.

CASE STUDY

Change in Flushing Schedule

The city of Gastonia’s Water Supply andTreatment Division conserved6,534,167 gallons of water during the2007 drought. It increased the timebetween backwashing the filters in thewater plant from 72 hours to 84 hoursand decreasing the time spent flushingwater lines in the distribution system.

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Understand YourWater Supplier’sWater Shortage PlanIn North Carolina, local government watersystems and other large community watersystems are required to develop a water short-age response plan. Facility managers shouldbe aware of these plans, participate in theirdevelopment and understand how they willaffect their operation during a water short-age. The specifics of each plan are unique foreach community. The chart on the followingpage lists key terms in a local water shortageplan.

CASE STUDY

Drought Measures

The N.C. Zoological Park’s Horticul-ture section saved water during the2007 drought by installing a new irri-gation control system, utilizing anevapotranspiration management sys-tem, which saved 1,541,568 gallons ofwater in just one growing season. Thezoo also repaired water leaks at twomajor pools, resulting in savings of be-tween 4,000 and 5,000 gallons per dayduring the drought. Furthermore, thezoo switched to an ozone water treat-ment system for two of its larger pools.This change has resulted in a reductionin the number of times a year that thesetwo pools need to be drained and re-filled from six times per year to twice ayear, saving a total of 250,000 gallonsper drain and fill.

CASE STUDY

Campus-wide Changes

The National Institute of Environmen-tal Health Sciences implemented sev-eral water conservation activitiesthroughout its campus to reduce itswater usage during the 2007-2008drought. With a campus covering 375acres, including a main administrativeand research laboratory building andseveral support service facilities, theefforts listed below resulted in consid-erable water savings.

Optimized chilled water system operationsto minimize cooling tower loadingIdentified and repaired utility system waterleaksEliminated outdoor wateringModified laboratory practices to minimizewater useUsed disposable trays and biodegradableutensils in the cafeteriaRetrofit lab autoclaves to minimize wateruseBegan installing waterless urinals as part ofa facility-wide replacement projectInstalled low-flow aerators on restroom,break room and lab faucetsModified washing procedures for laboratorysupport equipmentDisabled auto-flushing mode on commodesto eliminate false flushingEliminated support vehicle washingInstalled waterless hand sanitizers in allrestroomsDeferred water-consuming maintenanceand testing where possibleInvestigating and initiating design and instal-lation of long-term water conservation mea-sures such as condensate capture and re-use, low-flow commode installations andmunicipal gray water useEstablished internal water conservationWeb page and distributed drought updatesvia all-hands e-mail and electronic newslet-ters

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Key Terms in a Local Water Shortage PlanWater Use Classification: Water supplier will define a list of water uses and theirclassification. These classifications will typically fall into three categories:

Class 1: Essential : Those uses necessary for maintenance of public health andsafety.*Class 2: Socially or Economically Important: Those uses that fall between Class 1 and 3.Class 3: Non-essential: Water uses that can be restricted or totally banned withoutsignificant social or economic impact.

Levels of Water Shortage Severity: Local systems will define three stages orlevels of water shortage severities that include instructions and requirements. Levelsare determined by a specific measurement or “trigger” of available supply, demandand system condition.

Level 1: Voluntary Conservation: Conditions indicate potential for water supplyshortages; voluntary conservation is encouraged.Level 2: Mandatory Restriction: Water supplies are measurably lower than the sea-sonal norm and are diminishing. Mandatory restriction measures are imposed.Some mandatory levels will have multiple stages. Some local governments use theword “stage” in place of “level.”Level 3: Emergency Response: The system is experiencing a water shortage; drinkingwater supply is clearly inadequate, and more stringent restriction measures must beimposed.

Triggers: A trigger is a specific indicator of water supply storage based on an accu-rate assessment of available water supply. Triggers are used to initiate and removerestrictions. Triggers will be unique for each type of water supply (e.g., reservoir,run-of-river and groundwater) and will be established for each of the three levels ofwater shortage).

Enforcement: Local water supply plans will list existing or proposed ordinances,codes and regulations to enforce the measures of the plan. Facility managers shouldbe aware of penalties and enforcement activities.

Variances: The local water shortage plan should address the procedure to re-ceive variances to water use restrictions. There should be clear evaluation criteriaestablished for the review of these variances.

Emergency Price Rates: Some water suppliers will enact emergency pricingrates for water during severe drought levels. Find out if, how and when these ratechanges could affect your facility. Many water supply systems are moving towardpermanent conservation pricing rates, which increase with increased water usageor impose a demand surcharge on excess use.

*N.C. Session Law 2008-134 defined “essential water use” to include water necessary to satisfy federal, sate and locallaws for the protection of public health, safety, welfare and the environment and natural resources. It also includes “aminimum amount of water necessary to maintain the economy of the State, region or area.” The 2008-134 session lawalso increased authority of state officials to mandate local drought response actions.

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8 Definitions,Resources &References

DEFINITIONS*

Account A connection to a water system, which is billed for service.Acre-foot Enough water to cover an acre of land one-foot deep (i.e.,

325,851 gallons, or 43,560 cubic feet).Adjustment factor A decimal fraction used to modify reference evapotranspira-

tion to reflect an efficiency standard.Aerate, aerification Also called coring. Mechanical cultivation of turfgrass using

hollow tines to remove cores of turf, thatch and soil; improvessoil texture and increases air and water movement in root zone.

Allocation billing Used interchangeably with RUBS (see RUBS). Also, seeUtility Allocation.

Allocation types The basis by which utility expenses are apportioned to users.Common types include unit count, occupant count, occupantratio, square footage and a combination of occupant countand square footage. Less common types include bathroomcount and fixture count.

Apparent losses In a distribution system water audit apparent losses representthe “paper” losses that occur when volumes of water reach ause, but are not properly measured or recorded. They includecustomer meter inaccuracies, unauthorized consumption anddata handling error in customer billing systems. Apparent lossescause water utilities a loss of revenue but also interject adegree of error in the assessment of customer consumption,making it more difficult to evaluate the success of waterconservation and loss control measures.

Application rate The depth of water applied to a given area over time, usuallymeasured in inches per hour.

The definitions, units of measure and acronyms provided here are from the American Water Works Associaton’sWaterWiser program.

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Applied water The portion of water supplied by the irrigation system thatreaches the soil surface.

Appropriative water rights An exclusive right to take water as specified by the amount,source, use, location and period of time of its physical control.‘First in time, first in right.’

Area Square footage or acreage measured or estimated from scaleplans, photographs or from on-site measurements.

Arid climate A climate characterized by less than 10 inches of annualprecipitation.

As-built plans Site plans reflecting the actual constructed conditions of a land-scape irrigation system or other facility installation.

Avoided cost The cost of an activity or facility that could be avoided by choos-ing an alternative course of action.

Backflow prevention device A safety device used to prevent contamination of the potablewater supply from the reverse flow of water from an irrigationsystem or other customer activity back into the potable distri-bution system.

Backwash The use of water to clean filters. Water under high-pressure ispumped in reverse through filters, removing trapped sedimentand other material.

Ballcock A float actuated valve, part of the toilet trim in the toilet tankthat controls the refill water flowing into the toilet tank whenit is not full.

Beneficial rainfall The portion of total rainfall that is available for use by theplant (effective rainfall).

Best management practice A practice or combination of practices established as the mostpracticable means of increasing water use efficiency.

Bill stuffer An advertisement or notice included with a utility bill.Billing cycle The regular interval of time when customer’s meters are read

and bills are issued, generally every month (monthly) or twomonths (bi-monthly).

Billing period The elapsed time between two specific consecutive meter readsfor billing purposes.

Billing unit The unit of measure used to bill customers, either 100 cubicfeet (abbreviated HCF or CCF) or 1,000 gallons (kgals).

Bleed-off Draining off the water in a cooling tower reservoir to avoidthe buildup of excess dissolved solids. Also referred to asblowdown.

Blowdown Draining off the water in a cooling tower reservoir to avoidthe buildup of excess dissolved solids. Also referred to as bleed-off.

Blow-out toilet A type of toilet, normally found in hospitals or sites subject tohigh use, that has an extra wide trapway, is generally suppliedby at least a two-inch service line to the building, uses extrawater (with a powerful flush) to remove waste from the bowl.

Bluegrass A variety of cool-season turfgrass of the genus Poa. Commer-cially produced turfgrass mixes usually are a blend of bluegrassvarieties.

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Bubbler A type of sprinkler head that delivers a relatively large volumeof water to a level area where standing water graduallyinfiltrates into the soil. The flow rate is large relative to thearea to which the water is delivered. Bubblers are used toirrigate trees and shrubs.

Business Classification Code A numeric classification of customers into groups with similaruses or processes. See SIC code.

Calcium (Element abbreviation CA) A mineral that is commonly foundin water. It contributes to the hardness of water.

Capita Latin for ‘person.’Catch-can test Measurement of a sprinkler system’s application rate. Test

involves placing graduated containers at evenly spaced inter-vals throughout an irrigated area and measuring the depth ofwater collected in the cans over a given period of time.

Categorical variables Variables that are not scaled, but are “nominal,” that is, thereis no direction or number associated with the levels.

Central irrigation control A computerized system for programming irrigation control- system lers from a central location; using a personal computer and

radio waves or hard wiring to send program information togeographically distant controllers.

Check valve A device that prevents drainage of water down to the low pointsof an irrigation system after the system is shut off. Also calledanti-drain valve. A valve that allows flow in only one direc-tion, preventing backflow.

Class Customers having similar characteristics (commercial, single-family residential, etc.) grouped together for billing or programpurposes.

Climate factor Evapotranspiration minus precipitation. One of the fourfactors used to determine landscape water use.

Coliform bacteria Microorganisms (e.g., Escherichia Coli) common to theintestinal tract of warm blooded animals. The organisms’presence in water is an indicator of fecal pollution.

Commercial user Customers who use water at a place of business, such ashotels, restaurants, office buildings, commercial businesses orother places of commerce. These do not include multi-familyresidences, agricultural users or customers that fall within theindustrial or institutional classifications.

Commodity rate Charging for water based on the volume of use. Not a flat or fixed rate.

Compound meter A meter with two measuring chambers, generally a turbine forhigh flows and a positive displacement for low flows.

Conjunctive use The coordinated use and storage of surface and ground watersupplies to improve water supply reliability and potentiallyincrease the overall availability of water.

Connection fee A charge assessed to a new account by a water utility thatgenerally covers the cost of hooking up to the system andcompensates the utility for prior water system improvementsthat made the capacity available.

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Conservation rate structure A pricing structure billed by the quantity of commoditydelivered and tied to the costs associated with that delivery,designed to provide an accurate price signal to the consumer.An increasing block rate structure, if the top tier equals theutility’s marginal cost of new water, is one example of aconservation rate structure.

Consumer surplus The difference between what a commodity is worth to aconsumer and what she actually pays for it.

Continuous variables Variables that are numerical and can be scaled.Conversion factor A decimal fraction used to convert one unit of measure to

another, such as inches of depth over a square foot to gallons(0.623).

Cooling tower A mechanical device that cools a circulating stream of water byevaporating a portion of it. A cooling tower is part of a systemthat provides air conditioning or equipment cooling. Itusually includes a heat exchanger, recirculating water system,fans, drains and make-up water supply.

Cool-season grass Grass that does not ordinarily lose its color unless the averageair temperature drops below 32° F (0° C) for an extendedperiod; it is not usually damaged by subfreezing temperatures.Cool-season grasses grow actively in cool weather of springand fall and slowly in summer heat. Examples include blue-grass, fescue and ryegrass.

Coring Mechanical cultivation of turfgrass using hollow tines toremove cores of turf, thatch and soil; improves soil texture andincreases air and water movement in root zone. (SeeAerification.)

Cost-effective When the present value of benefits exceeds the present valueof costs.

Cost-effectiveness An analysis that compares the financial benefits of watersavings to the costs needed to achieve those savings.

Costs The resources needed for a course of action.Crop coefficient A factor used to adjust reference evapotranspiration and

calculate water requirements for a given plant species. (Alsocalled plant factor or landscape coefficient.)

Curb stop Shut-off valve between the customer meter and the street ser-vice line from the water main.

Customer class A group of customers (residential, commercial, industrial,wholesale and so on) defined by similar characteristics orpatterns of water usage.

Declining block rate A commodity rate whose unit price decreases with increasingwater use.

Dedicated metering Metering of water service based on a single type of use, such asmetering for landscape irrigation separately from interiordomestic use.

Demand management Measures, practices or incentives deployed by utilities to changethe pattern of demand for a service by its customers or slowthe rate of growth for that service.

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Demand side measures In the water industry, programs which encourage customersto modify the amount or timing of water use. These measuresmay include encouraging customers to implement hardwareor behavior changes, or change the volume or timing of theiruse, depending on the time of day or time of year.

Desalination The process of removing salt from brackish water or sea water,producing water suitable for fresh water uses and a concen-trated brine.

Developed water Water that has been captured in reservoirs, diverted fromrivers/streams or accessed by wells for use by society.

Discount rate The financial rate used to calculate the present value of futurebenefits and costs.

Distribution facilities Pipes, meters, storage, pumps and other facilities used todistribute water to end users.

Distribution uniformity An expression of how evenly water is applied to a landscape byan irrigation system. DU is calculated in the field by analyzingthe results of catch-can tests.

Door hanger An advertisement, notice or product hung on a resident’sdoorknob – often used to promote customer participation inwater conservation programs.

Door-to-door-drop-off Refers to a method of retrofit kit delivery involving a person or canvas leaving a kit at the door and, in the case of a canvas, returning

later to offer installation assistance or verify owner installation.Drip irrigation The slow, accurate application of water directly to plant root

zones with a system of tubes and emitters usually operatedunder reduced pressure.

Drought An extended period of below-average precipitation resultingin a reduction of water in available storage that can result in acutback in water service to customers.

Dual and multiple The capacity of an irrigation controller to schedule the programming frequency and duration of irrigation cycles to meet varying

water requirements of plants served by a system. Groupingplants and laying out irrigation stations by similar waterrequirements facilitates multiple programming.

Dye test A test for water leaks, specifically by putting dye in a toilettank to see if it appears in the bowl.

Effective precipitation The portion of total rainfall that is available for use by theplant.

Efficiency standard A value or criteria that establishes target levels of water use fora particular activity.

Effluent Something that flows out, such as wastewater, treated oruntreated, that flows out of a wastewater treatment plant, seweror industrial outfall.

Emitter A drip irrigation component that dispenses water to plants ata known rate, measured in gallons per hour.

End use A fixture, appliance or other specific object or activity thatuses water.

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Escalation rate The average rate of increase in the inflation-adjusted futurecost of water supply.

Estimated water use The amount of water estimated to be needed by the landscapeduring one year.

Estuary The lower course of a river where its flow is commingled bythe sea, resulting in brackish water.

ET factor A factor used to set a landscape water efficiency goal. Alsoknow as an “adjustment factor.”

Evapotranspiration The quantity of water evaporated from soil surfaces andtranspired by plants during a specific time.

External costs and benefits An external cost is when one party adversely affects anotherparty either by reducing its productivity or well being. Anexternal benefit is where one party beneficially affects anotherparty either by increasing its productivity or its well being, orlowering its costs.

Externalities External costs and benefits.Faucet aerator A flow reduction device that screws on the end of the kitchen

or lavatory faucet to add air to the water flow.Fecal coliform The coliform bacteria group that are present in the intestinal

tracts and feces of humans and other warm-blooded animals.Drinking water with fecal coliform can cause diarrhea and othergastrointestinal illnesses.

Filtration A water treatment process that involves water passing throughsand or other media, where particles and other constituentsare trapped and removed from the flow.

Fixed costs Costs that do not change as output level changes over the timehorizon being analyzed.

Fixed rates Part of a utility bill that is not affected by consumption.Flapper valve A pliable valve in the opening at the bottom of a toilet tank

that regulates water flow into the toilet bowl.Flow rate The rate at which a volume of water flows through pipes, valves,

etc. in a given period of time. Often reported as cubic feet persecond (cfs) or gallons-per-minute (gpm).

Flush valve A valve used to expel sediment from irrigation lines. Also, atype of flushing mechanism used in commercial toilets.

Flushometer A commercial/institutional type toilet, which generates a flushby the opening of a valve directly connected to the pressurizedbuilding water system.

Graywater Untreated (or lightly treated) domestic effluent, not includingwater from toilets or the kitchen, for use on the property insubsurface landscape irrigation.

Green industry The trades, professions and disciplines related to landscapeand irrigation research, design, installation and management.

Groundwater Water that has seeped beneath the earth’s surface and is storedin the pores and spaces between alluvial materials (sand, gravelor clay).

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Groundwater banking Storing surface water in a groundwater basin, or using surfacewater in lieu of groundwater, to increase the available ground-water supply.

Groundwater recharge Percolating or injecting surface water into a groundwaterbasin to increase the available groundwater supply.

Hardscape Landscaping that does not permit water to seep into the ground,such as concrete, brick and lumber.

Hardware efficiency A percentage or fraction value that represents the portion ofwater applied by an irrigation system that is beneficial to theplants. See distribution uniformity.

H-axis clothes washer Horizontal-axis clothes washer.High-efficiency clothes A type of clothes washer meeting certain water and energy washer standards. It often involves a design where the tub axis is

more nearly horizontal than vertical. Clothes are tumbledthrough water that only fills a fraction of the tub. Also knownas a horizontal axis, tumble action or front-loading clotheswasher.

High-water-using plants Plants with a crop coefficient greater than 0.7.Historic basis Past water consumption history.Hot water hybrid The practice of estimating a resident’s total water usage based

on metered hot water usage.Hot water on demand system A system of pumping hot water more quickly from the water

heater to the fixture calling for water for the purpose of reduc-ing the wait time (and associated waste) for hot water.

Hot water ratio billing The practice of estimating a resident’s total water usage basedon metered hot water usage.

Hydrologic cycle Movement of water as it evaporates from rivers, lakes or oceans,into the atmosphere, returns to earth as precipitation, flowsinto rivers to the ocean and evaporates again.

Hydrozone A portion of the landscaped area having plants with similarwater needs that are served by a valve or set of valves with thesame schedule.

Impact head A type of single-stream rotor that uses the impact of a streamof water to rotate a nozzle in a full or partial circle. Impactheads have large radii and relatively low precipitation ratesand do not provide matched precipitation rates for varying arcpatterns.

Inclining block rate A commodity rate whose unit price increases with increasingwater use.

Incremental benefits and The next unit of cost required to achieve the next unit of costs benefit.Individual metering The installation of meters for each individual dwelling unit as

well as separate common area metering with the local waterutility providing customer read, bill and collect services.

Industrial user Water users that are primarily manufacturers or processors ofmaterials as defined by the Standard Industrial ClassificationsCode numbers 2000 through 3999.

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Infiltration rate The rate at which water permeates the soil surface, expressedas a depth of water per unit of time (inches-per-hour).

Inflation The rate of change in a price index.Infrastructure Leakage Index In a water supply distribution system, the Infrastructure Leak-

age Index, ILI, is the ratio of the current level of annual real losses (mostly leakage) to the Unavoidable Annual Real Losses,UARL. It is a good benchmarking performance indicator forcomparisons of leakage standing among drinking water utilities.

Institutional user Water-using establishment dedicated to public service. Thisincludes schools, churches, hospitals and government facili-ties. All facilities serving these functions are considered insti-tutional regardless of ownership.

Instream uses The beneficial uses of water within a river or stream, such asproviding habitat for aquatic life, sport fishing, river raftingor scenic beauty.

Irrigated area The portion of a landscape that requires supplemental irriga-tion, usually expressed in square feet or acres.

Irrigation controller A mechanical or electronic clock that can be programmed tooperate remote-control valves to control watering times.

Irrigation cycle A scheduled application of water by an irrigation stationdefined by a start time and its duration. Multiple cycles can bescheduled, separated by time intervals, to allow infiltration ofapplied water.

Irrigation efficiency A value representing the amount of water beneficially applied,divided by the total water applied. Also, the product of deci-mal equivalents representing hardware efficiency and manage-ment efficiency.

Irrigation only accounts Accounts with a separate meter dedicated to non-sewered usessuch as landscape irrigation or cooling towers.

Irrigation plan A two-dimensional plan drawn to scale expressing the layoutof irrigation components and component specifications. Lay-out of pipes may be depicted diagrammatically, but location of irrigation heads and irrigation schedules should be specified.

Irrigation scheduling The process of developing a schedule for an automatic irriga-tion system that applies the right amount of water, matched to the plant needs, which varies daily, weekly or seasonally.

Irrigation station A group of irrigation components, including heads or emit-ters and pipes, controlled/operated by a remote control valve.

Landscape irrigation auditor A person who has had landscape water audit training andpassed a certification exam.

Landscape water budget A volume of applied irrigation water expressed as a monthlyor yearly amount, based on ETo and the plant material beingwatered.

Law of the River A collection of interstate agreements, international treaties,legislation and judicial decisions that form the basis of alloca-tion decisions for the Colorado River.

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Leak correlator An electronic device that uses probes placed on exposedportions of a water distribution system to pinpoint the loca-tion of a leak.

Leak detection The procedure of pinpointing the exact location of leaks fromwater pipes and fittings.

Leakage management The organized, proactive functions of a water utility to controldistribution system leakage to a economic minimum. Includesappropriate combinations of active leakage control (flow analy-sis, leak detection) and repair, pressure management andsystem rehabilitation.

Leak noise logger A device that gathers and stores sounds used in detecting andpinpointing water distribution system leaks across a given areaof the system

Leak survey The systematic process of listening for leaks in a distributionsystem.

Life-cycle analysis Examines the costs and benefits of an action over its entireexpected life span.

Limited turf areas Restriction of turfgrass to a prescribed fraction of the land-scape area.

Low flow detector A part of a water meter register that indicates any flow throughthe meter. Also, called a Leak Indicator.

Low flow faucet A faucet fixture that meets 1992 EPAct standards (2.2 gpm orless at 80 psi).

Low flow showerhead A showerhead that meets 1992 EPAct standards (2.5 gpm orless at 80 psi).

Low flow toilet A 3.5 gpf toilet, as mandated by California in a 1977 law thattook effect 1980.

Low head drainage Drainage of water from irrigation lines at the lowest elevationsin an irrigation station.

Lower basin states The states of Nevada, Arizona and California, which form partof the Colorado River watershed.

Low-water-using plants Plants with a crop coefficient of less than 0.3.Makeup water Fresh water introduced into a cooling tower to replace water

lost to evaporation and blowdown.Management efficiency A percentage or fraction of the total applied water that repre-

sents the portion beneficially applied. This is determined byscheduling, maintenance and repair of irrigation systems.

Marginal cost The additional cost incurred by supplying one more unit ofwater.

Market price The price for a commodity in a market.Mass mailing Mailing information or retrofit kits to many customers – often

using a mailing service.Master meter A single meter that measures utility usage for an entire prop-

erty, or an entire building, which usually includes commonareas.

Matched precipitation rates Equal water-delivery rate by sprinkler heads with varying arcpatterns within an irrigation station. Matched precipitationrates are required to achieve uniform distribution.

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Matched sprinkler heads Sprinkler heads with the same precipitation rate.Mediterranean climate A climate characterized by moderate temperatures throughout

the year, dry summers and rainy winters.Medium-water-using plants Plants with a crop coefficient of 0.4 to 0.6.Meter Device that measures utility usage.Meter (water) An instrument for measuring and recording water volume.Meter register Mechanical device (sometimes used synonymously with the

term “Face”) that uses a system of gear reductions to integratethe rotation of the moving element of a meter’s measuringchamber into numerical units.

Microclimate The climate of a specific place within a given area, generallyvarying by wind and evapotranspiration.

Mixed use meter A water meter that serves more than one type of end use, suchas an office building and its surrounding landscape.

Mulch A protective covering of various substances, usually organic,such as wood chips, placed on the soil surface around plantsto reduce weed growth and evaporation and to maintain eventemperatures around plant roots.

Multi-family Residential housing with multiple dwelling units, such as apart-ments and condominiums.

Multiple linear regression Method of determining the relationship between several inde-pendent or predictor variables and a dependent variable. Thedependent variable must be a continuous variable.

Multiple start times An irrigation controller’s capacity to accept programming ofmore than one irrigation start-time per station per day.

Municipal and industrial Water supplies serving humans or man-made activities, asopposed to agricultural water supply.

NAICS (formally SIC codes) North American Industry Classification System. A consolida-tion of the codes for the U.S., Canada and Mexico. Producedby the U.S. Office of Management and Budget.

Native and adopted plants Plants indigenous to an area or from a similar climate thatrequire little or no supplemental irrigation once established.

Net present value The present value of benefits minus the present value of costs.Non-potable water Water that does not, or may not, meet drinking water quality

standards.Non-revenue water In a distribution system water audit, non-revenue water equals

the volume of unbilled authorized consumption (water for firefighting, system flushing and similar uses) added to real lossesand apparent losses.

O&M Operation and maintenance.Off-stream Water use occurring outside the natural stream channel.Operating pressure Distribution system water pressure measured in pounds-per-

square-inch (psi). Municipal systems are generally maintainedbetween 50 and 80 psi.

Opportunity costs The true costs faced by a decision maker, measured as the high-est valued alternative that is foregone when an action is taken.

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Overdraft A groundwater basin is being overdrafted when, over a num-ber of years, the average amount of water withdrawn from thebasin exceeds the average amount of water flowing into the basin.

Overspray Application of water via sprinkler irrigation to areas other thanthe intended area.

Partial-capture submetering Type of submetering where only a portion of the total waterconsumption in each unit is measured.

Peak use The maximum demand occurring in a given period, such ashourly or daily or annually.

Per capita residential use Average daily water use (sales) to residential customers dividedby population served.

Per capita use Water use per person.Percent switch A feature of an irrigation controller that allows percent changes

in the duration of programmed irrigation.Plant factor See crop coefficient.Point-of-use meter A meter that measures water flow at the actual usage point,

such as a faucet or toilet.Positive displacement meter A type of water meter used to measure relatively low flows

(such as residential uses).Potable water Water that meets federal and state water quality standards for

water delivered to utility customers.Pounds-per-square-inch A unit measure of pressure. In this case, the pressure exerted

by water in a distribution system.Precipitation rate Application rate for sprinkler irrigation, generally measured

in inches-per-hour.Pressure assist toilet A toilet that uses the water distribution system pressure to

compress air in a bladder that fills with water after the toilet isflushed. The compressed air forces the water from the bladderinto the toilet bowl at an increased velocity.

Pressure loss The reduction in water pressure due to friction of water againstthe inner walls of pipe and components.

Pressure reducer A water system component that reduces the downstreampressure of water, often used in irrigation systems, always usedin drip systems.

Pressure regulation Maintaining distribution system water pressure within certainlimits.

Pressure regulating valve 1) A device, often installed downstream of the customer meter,to reduce high pressures to a set amount. Often required wherethe existing system pressure exceeds 85 psi. 2) A device in-stalled on input water supply mains or irrigation systems toregulate water pressure in a zone or district metered area toprotect against pressure surges and to control leakage.

Pressure testing Subjecting a fully loaded section of a water distribution systemto maximum normal pressure (or normal pressure plus a safetyfactor) against a closed downstream shut-off.

Pressure zone A three dimensional zone in the water distribution system wherethe pressure is allowed to vary only within certain limits, generallydictated by the elevation of the water tank serving the zone.

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Pressure-compensating A drip-irrigation emitter designed to deliver water at a consis- emitter tent flow rate under a range of operating pressure.Primary treatment The first stage of a wastewater treatment process in which float-

ing material and large suspended solids are removed bymechanical processes, such as filtration.

Public service announcement An inexpensive or free advertisement or message on mass mediathat serves the public good.

Public Trust Doctrine Doctrine rooted in Roman law, which holds that certain natu-ral resources are the property of all, to be held in trust for thecitizens by the state.

Public user Publicly owned water customers, such as schools, parks andgovernment buildings. Also referred to as institutional customers.

Rain shutoff device A device connected to an irrigation controller that overridesscheduled irrigation when significant precipitation is detected.

Raw water Untreated water.Real losses In a water distribution system audit, real losses are the physi-

cal loss of water from the distribution system prior to reachingthe customer. Real losses include leakage from piping andreservoir walls, as well as storage overflows caused by faultycontrol equipment or operator error. Real losses represent awaste of water and energy resources since they are volumes ofwater extracted from a source, treated to prevailing standards,but never reaching beneficial use.

Receiver In a radio frequency based AMR system, the device that receives the meter data transmissions for the central data collec-tion device.

Recirculating task Water that is employed for the same task multiple times. In acooling tower, water is used to carry heat away from a heatsource, cooled by evaporation in a cooling tower and returnedto the heat source to repeat the task.

Reclaimed water Municipal wastewater effluent that is given additional treat-ment and distributed for reuse in certain applications. Alsoreferred to as recycled water.

Reclamation (water) Treatment of degraded water for a beneficial purpose.Recycled water Used to describe reclaimed water.Reference evapotranspiration The water requirements of a standardized landscape plot,

specifically, the estimate of the evapotranspiration of a broadexpanse of well-watered, 4-to-7 inch-tall cool-season grass.

Remote-control valve An electric solenoid valve, wired to an irrigation controller,that controls the flow of water to an irrigation station.

Repeater In a radio frequency based AMR system, the device thatreceives and amplifies the meter RF signals in order to trans-mit them to the receiver.

Retention rate The percent of devices that remain in-place over time afterinitially being installed or distributed.

Retrofit 1) Replacement of existing water using fixtures or appliances withnew and more efficient ones. 2) Replacement of parts for a fix-ture or appliance to make the device more efficient.

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Retrofit on resale A regulation that requires plumbing fixtures to be upgraded tocurrent code at the time property is sold.

Reuse Use of treated municipal wastewater effluent for specific,direct, beneficial uses. See reclaimed water. Also used todescribe water that is captured on-site and utilized in a newapplication.

Reverse osmosis A process to remove dissolved solids, usually salts, from water.Salty water is forced through membranes at high pressure,producing fresh water and a highly concentrated brine.

Riparian rights A water right based on the ownership of land bordering a riveror waterway.

Runoff Surface flow of water off of a specific area.Seasonal block rate A commodity rate that is higher in the peak irrigation season

than the off-peak season.Secondary treatment The second step in most wastewater treatment systems, which

removes most of the oxygen-demanding substances (organics)and light suspended solids. Disinfection is often the final stepof secondary treatment.

Secondary wastewater A facility that employs secondary wastewater treatment. treatment plantSemiarid climate A climate characterized by 10 to 20 inches of annual

precipitation.Sensitivity analysis The process where the assumptions of analysis are tested to

determine how much influence they have on the results.Service area (territory) The geographic area(s) served by a utility.Short-term program A temporary water conservation program put in place to deal

with a specific concern such as a water shortage.SIC Code A system devised by the federal government to classify indus-

tries by their major type of economic activity. The code mayextend from two to eight digits. This term has been super-ceded by the NAICS.

Single-family unit A residential dwelling unit built with the intent of beingoccupied by one family. It may be detached or attached (i.e.,townhouses).

Soil amendment Organic and inorganic materials added to soils to improve theirtexture, nutrients, moisture holding capacity and infiltrationrates.

Soil improvement The addition of soil amendments.Soil polymer A natural or synthetic compound that has the capacity to hold

water for use by plants. Best suited for container plants or insandy soil. Can reduce irrigation frequency but does notreduce a plant’s water requirement.

Solar radiation Energy from the sun. The single most dominant factor indetermining ET values, measured by a lysimeter.

Spray head A sprinkler irrigation nozzle installed on a riser that deliverswater in a fixed pattern. Flow rates of spray heads are highrelative to the area covered by the spray pattern.

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Spray irrigation Sprinkler irrigation using spray heads on fixed or pop-uprisers and having relatively high precipitation rates.

Sprinkler irrigation Overhead delivery of water spray heads, stream rotors orimpact heads. Precipitation rates will vary depending onsystem layout and type of head used.

Sprinkler run time The minutes of irrigation per day, based on the weekly irriga-tion requirement and irrigation days per week.

Sprinkler station A group of sprinklers controlled by the same valve.Sprinkler valve The on-off valve, usually electric, that controls an irrigation or

sprinkler station.Station An irrigated area controlled by a single irrigation valve.Storm drainage Surface runoff of water resulting from rain or snow storms.Stream rotors Sprinkler irrigation heads that deliver rotating streams of

water in full or partial circles. Some types use a gear mecha-nism and water pressure to generate a single stream ormultiple streams. Stream rotors have relatively low precipita-tion rates, and multiple stream rotors can provide matchedprecipitation for varying arc patterns.

Structured plumbing system Properly sized and well insulated hot water main and hotwater risers, including a dedicated hot water main segmentconnecting the farthest hot water point of use to the waterheater.

Submetering The practice of using meters to measure master-metered utilityconsumption by individual users. Also, see partial-capturesubmetering and total-capture submetering.

Subsidence The lowering of ground surface due to extraction of materialfrom subsurface. Can be caused by water or oil extraction fromthe ground.

Subsurface drip irrigation The application of water via buried pipe and emitters, withflow rates measured in gallons-per-hour.

Sunken costs Costs that have already been incurred and are not reversible.Supply-side measures Increasing water supply by developing more raw water, gener-

ally building reservoirs and canals or drilling groundwater wells.Surface water Water that remains on the earth’s surface, in rivers, streams,

lakes, or reservoirs.Tall fescue A hybridized cool-season turfgrass characterized by deeper roots

and more drought tolerance than bluegrass.Telemetry interface unit A device that translates meter data prior to transmission to a

receiver. Also known as a Meter Interface Unit.Thatch The buildup of organic material at the base of turfgrass leaf

blades. Thatch repels water and reduces infiltration capacity.Toilet flapper A pliable valve in the opening at the bottom of a toilet tank

that regulates water flow into the toilet bowl.Toilet tank fill cycle regulator A device that reduces the amount of water that goes into the

overflow tube and hence into the toilet bowl during a toilet flush.Total-capture submetering Type of submetering where all of the actual water consump-

tion in each unit is measured.

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Transmitter A radio frequency system component that sends usage datafrom a meter to a receiver.

Transpiration The passing of water through living plant membranes into theatmosphere.

Trihalomethanes Four chemicals that are a reaction byproduct when chlorine isadded as a disinfectant to water containing certain organicmaterial. These chemicals are called disinfection byproductsand are regulated by the U.S. EPA. Some of them are suspectedcarcinogens.

Turbine meter A type of water meter that generally utilizes a propeller tomeasure high flows (such as for irrigation or commercial/industrial users).

Turfgrass Hybridized grasses that, when regularly mowed, form a densegrowth of leaf blades and roots.

Unavoidable annual The low level of leakage that a well managed water distribu- real losses tion system could, in theory, attain assuming that state-of-the-

art leakage control technologies are being effectively utilized.A calculation exists to determine the UARL and includes milesof water main, average system pressure and number of serviceconnections as input parameters. The ratio of current annualreal losses over the UARL gives the Infrastructure Leakage Index.

Ultra low flush toilet A toilet that flushes with 1.6 gallons or less.Uniform block rate A commodity rate that does not vary with the amount of water

use.Uniformity See distribution uniformity.U.S. Bureau of Reclamation Federal agency that built and operates water projects in the

western United States. Part of the Department of Interior.Unmetered water Delivered water that is not measured for accounting and

billing purposes.UPC The model plumbing code, prepared by International Associa-

tion of Plumbing and Mechanical Officials, that the 22 west-ern States use as the basis for their State plumbing codes.

Upper basin states The states of Wyoming, Colorado, Utah and New Mexicowhich form part of the Colorado River watershed.

Usable groundwater storage The quantity of additional space available for water storage ina groundwater basin without outflow.

User class Customers having similar characteristics (commercial, single-family residential, etc.) grouped together for billing or programpurposes.

Utility Used alternately to describe a provided resource, such aswater, gas, electric as well as for the provider of the resource

Utility allocation Determining resident charges for utilities by means of aformula rather than measured usage.

Valve Device to control the flow of water.Variable costs The costs that change in response to changes in level of output.

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Warm-season grass Grasses that grow vigorously in warm summer months andthen generally lose their green color and are dormant inwinter, if the average air temperature drops below 50 to 60° F;some may die if exposed to subfreezing temperatures forextended periods. Examples of warm season grasses includeBermuda, Zoysia and Buffalo grasses.

Wastewater Effluent water from residences, businesses and other waterusers that contains contamination. Sewage.

Wastewater treatment plant A facility designed to remove contamination from municipaland industrial wastewater prior to discharge into surfacewaters.

Water allowance The quantity of water needed to maintain plants and otherfeatures in an ornamental landscape.

Water audit 1) An on-site survey of an irrigation system or other water usesetting to measure hardware and management efficiency andgenerate recommendations to improve its efficiency. 2) Forwater distribution systems, a thorough examination of theaccuracy of water agency records and system controlequipment to identify, quantify and verify water and revenuelosses.

Water banking A process whereby unused water allocations are held instorage and made available for future water allocations.

Water budget The quantity of water needed to maintain plants and otherfeatures in an ornamental landscape.

Water budget approach A method of establishing water-efficiency standards for land-scapes by providing the water necessary to meet the ET of thelandscaped area.

Water conservation The U.S. Water Resources Council defines water conserva-tion as activities designed to (1) reduce the demand for water,(2) improve efficiency in use and reduce losses and waste ofwater, and (3) improve land management practices to conservewater.

Waterless urinal A urinal that works without water or flush valves. Instead acartridge filled with a sealant liquid is placed in the drain. Thelighter than water sealant floats on top of the urine prevent-ing odors from being released into the air and allowing urineto pass into the sewer system without the use of water. Theurinals are installed into the regular waste lines and thecartridge and sealant must be periodically replaced, but watersupply lines and flush valves are not necessary. The urinalbowl surfaces are urine repellent and daily cleaning proceduresare typically the same as for flushed urinals.

Water meter size Normally corresponds to the pipe bore, for example 1”. Forsome models a second designation refers to the matching pipeend connections. For example, a 5/8” x 3/4” meter has a nomi-nal 5/8” and 3/4” straight pipe threads.

Water rationing Mandatory water restrictions temporarily placed on customers,as with short-term or drought programs.

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Water reuse Use of treated municipal wastewater effluent for specific,direct and beneficial uses. See reclaimed water. Also used todescribe water that is captured on-site and utilized in a newapplication.

Water right A legal entitlement authorizing water to be diverted from aspecified source and put to beneficial, non-wasteful use. It is aproperty right, but the holder doesn’t possess the water itself –they possess the right to use it. The primary types of waterrights are appropriative and riparian. There are also prescrip-tive (openly taking water to which someone else has the right)and pueblo (a municipal right based on Spanish and Mexicanlaw) water rights.

Water sales Water deliveries that are metered and billed based on the quan-tity of use.

Water softener A device that reduces water hardness by replacing calcium andmagnesium ions with sodium ions.

Water transfers The exchange of a water allocation from a willing seller to abuyer, usually between irrigation district (seller) and urban wateragency (buyer).

Water use efficiency A measure of the amount of water used versus the minimumamount required to perform a specific task. In irrigation, theamount of water beneficially applied divided by the totalwater applied.

Water use profile A quantitative description (often displayed graphically) of thedifferent water uses at a residence, business site or utilityservice area.

Water-efficient landscape A landscape that minimizes water requirements and consump-tion through proper design, installation and management.

Watershed A land area, defined by topography, soil and drainage charac-teristics, within which raw waters are contained. They cancollect to form a stream or percolate into the ground.

Waterworks bronze Refers to one of two generally accepted alloys, one with a nomi-nal composition of 81% copper, 3% tin, 7% lead and 9% zincor another with a nominal composition of 85% copper, 5%each tin, lead and zinc.

Wetlands A lowland area, such as a marsh or swamp, that is saturated withmoisture, and often the natural habitat of abundant wildlife.

Wetting area (pattern) The soil area wetted by a sprinkler, bubbler or low-volumeemitter.

Wholesale water agency A water utility that develops and distributes water not fordelivery to individual customers, but to other retail waterpurveyors.

Willingness to accept The amount one would have to pay an individual if she couldbe induced by a payment to go without an item.

Willingness to pay The amount an individual would be willing to pay if she couldobtain the item by making a payment.

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Xeriscape Landscaping practice based on seven principles: properplanning and design; soil analysis and improvement; practicalturf areas; appropriate plant selection; efficient irrigation;mulching; and appropriate maintenance.

Zero footprint The complete reduction and/or offset of the potable waterdemand of a proposed urban development project by conser-vation, use of recycled water or other measures.

Zero read test A test for water leakage on customer piping using a feature ofthe customer’s water meter.

Units of Measurementaf acre-feet, = 325,851 gallons or 43,560 cubic feetafa acre-feet per annum (year)BTU British Thermal Unitccf Hundred cubic feet = 748 gal.cf Cubic feet = 7.48 gal.gal Gallons, 1 gallon = 0.134 cubic feetgcd Gallons per capita per daygpcd Gallons per capita per daygpd Gallons per daygpf Gallons per flush (of a toilet or urinal)gpm Gallons per minutegpsf Gallons per square foothcf Hundred cubic feet = 748 gal.hr Hourskgal One thousand gallons = 134 cubic feetkWh Kilowatt-hoursl Literslcd Liters per capita per daylpf Liters per flush (of a toilet or urinal)MG Million gallonsmgd Millions of gallons per dayMG/yr Millions of gallons per yearmin. minutepsi Pounds per square inchsf Square feet

AcronymsAC Alternating currentASCE American Society of Civil Engineers, www.asce.orgAMR Automatic meter reading equipmentANSI American National Standards Institute, www.ansi.orgARM Automated remote meteringASME American Society of Mechanical Engineers, www.asme.orgAWC Average winter consumption

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AWR Applied water requirement, the gross amount of water that must be appliedto a plant or grass to accommodate evapotranspiration including runoff andwater required to overcome system efficiencies

AWWA American Water Works Association, www.awwa.orgAwwaRF American Water Works Association Research Foundation, www.awwarf.orgBMP Best management practiceCALFED A joint effort by state and federal agencies to resolve water supply and quality

issues involving the San Francisco Bay and Sacramento-San Joaquin DeltaCC&Rs Conditions, covenants and restrictionsCEE Consortium for Energy Efficiency, www.cee1.orgCI Commercial and industrialCII Commercial, industrial and institutionalCIMIS California Irrigation Management Information System, www.cimis.water.ca.govCIS Customer information systemCUSTID Customer identification numberCUWCC California Urban Water Conservation Council. Formed in 1991 with a memo-

randum of understanding between water agencies and public interest groupsregarding the implementation of cost-effective urban water conservation mea-sures in California. A voluntary, non-regulatory organization. www.cuwcc.org

DC Direct currentDCU Data collection unit (in an AMR system)DU Dwelling unitDU Distribution uniformity- a measure of irrigation efficiencyDEIR Draft Environmental Impact ReportEF Energy factorEGLS Estimated generalized least-squaresEIS Environmental Impact StatementEPA Environmental Protection Agency, www.epa.govEPAct Energy Policy Act, first implemented in Oct. 1992ER Effective rainfallET Evapotranspiration, water loss via evaporation from plant surfaces and soil

at base of plant and transpiration from plant leaf or grass surfacesETo Reference ET for a standard crop of grass 4 inches to 7 inches tallHD High density, refers to MF and other types of units constructed in dense

configurationHOA Homeowners associationHUD U.S. Department of Housing and Urban Development, www.hud.govIA Irrigation Association, www.irrigation.orgIE Irrigation EfficiencyILI Infrastructure Leakage IndexIRP Integrated resources planningKL Landscape coefficient (includes crop coefficient, and coefficients for shade

and slope)LF Low-flowLEED Leadership in Energy and Environmental Design (U.S. Green Bldg Council,)

www.usgbc.org/LEEDLID Low-impact development (for storm water quality)

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MaP Maximum performance testing (of toilets and other fixtures). This is atrademarked label.

MEF Modified energy factorMF Multi-family dwelling unitMFR Multi-family residentialMIU Meter interface unit. Also known as a Telemetry Interface Unit.N Number. The number of cases from which a summary statistic or analysis is

derived.NIST National Institute of Standards and Technology, www.nist.govNPV Net present value of a series of payments, costs or benefitsP-value The probability value of a statistical hypothesis test; the probability of

getting a value of the test statistic as extreme or more extreme than thatobserved by chance alone, if the null hypothesis is true

PAC Project advisory committeePOC Project oversight committeePOU Point of usePUC Public utilities commissionPV Present value of a series of payments, costs or benefitsOLS Ordinary least squaresR 2 Coefficient of determinationRBC Read, bill and collectREUWS Residential End Uses of Water Study (AWWA 1999)RF Radio frequencyRMSE Root mean square errorRUBS Ratio utility billing systems, a calculation method that uses a compensation

factor to allocate utility costs among users, most often used in the context ofmulti-family or commercial billing

SCS Soil Conservation Service now Natural Resources Conservation Service,www.nrcs.usda.gov

SF Single-family dwelling unit (detached unless otherwise specified)SWAT Smart Water Application Technology: class of irrigation controllers using soil,

weather or ET-based measurements to control irrigation schedulingSt. Dev. Standard deviationSUR Seemingly unrelated regressionSWRS Subregional water reclamation systemt-test An inferential statistical test for comparing two means. A dependent or paired

t-test is used to compare the mean difference score between paired measurementsUARL Unavoidable annual real lossesULF Ultra-low flowULFT Ultra-low flow toilet. Standard "low consumption toilets." Refers to toilets which

consume 1.6 gallons (6 liters) or less of water when flushed. A bit of a misnomeras toilets do not "flow" unless they are broken and are wasting water.

UNAR Unified North American Requirements for toilet fixtures (and other devices)WD Water districtWF Water factorWW Wastewater

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North Carolina Assistance ProvidersAddressing Water Efficiency, Pollution Preven-tion and Energy Efficiency

N.C. Division of Pollution Prevention and Environ-mental AssistanceN.C. Department of Environment and Natural Re-sources1639 Mail Service CenterRaleigh, NC 27699-1639Phone: (800) 763-0136Web site: http://www.p2pays.orgThe North Carolina Division of Pollution Prevention andEnvironmental Assistance provides free, non-regulatory on-site pollution prevention assessments, including water effi-ciency to businesses, industries and municipalities in NorthCarolina. DPPEA resources also include technical fact sheetsand manuals on pollution prevention and a clearinghouseof more than 44,000 references. A matching grant programis also available for innovative pollution prevention andwater efficient technologies.

N.C. State Energy OfficeN.C. Department of Administration1340 Mail Service CenterRaleigh, NC 27699-1340Phone: (800) 662-7131Web site: http://www.energync.netThe North Carolina State Energy Office provides energyinformation and assistance for businesses, government agen-cies, community colleges, universities, schools and the resi-dential, commercial and industrial sectors.

N.C. Division of Water ResourcesN.C. Department of Environment and Natural Re-sources1611 Mail Service CenterRaleigh, NC 27699-1611Phone: (919) 733-4064Web site: http://www.ncwater.orgThe Division of Water Resources provides technical assis-tance to water systems with water supply planning, leakdetection, water conservation and water shortage responseplanning.

RESOURCES

N.C. Solar CenterN.C. State UniversityCollege of EngineeringBox 7401Raleigh, NC 27695-7401Phone: (800) 33-NCSUNWeb site: http://www.ncsc.ncsu.eduThe N.C. Solar Center offers assessments of potential re-newable energy applications for commercial and industrialsites. Often conducted in conjunction with surveys to iden-tify savings in energy, productivity and waste by the NCSUIndustrial Assessment Center and the IES Energy Manage-ment Program, the Solar Center’s assessments focus on prac-tical ways companies can incorporate renewable energy.

N.C. State University’s Industrial Extension ServiceN.C. State UniversityCollege of EngineeringRaleigh, NC 27695Phone: (919) 515-2358Web site: http://www.ies.ncsu.eduN.C. State University's Industrial Extension Service canprovide energy audits and energy conservation courses for asmall fee. This assistance targets nearly all basic unit op-erations of a manufacturing facility ranging from compres-sors to HVAC units.

N.C. State University’s Industrial Extension ServiceManufacturing Extension PartnershipCollege of EngineeringRaleigh, NC 27695Phone: (800) 227-0264Web site: http://www.mep.nist.govThe N.C. Manufacturing Extension Partnership team of engi-neering specialists offers technical assistance to North Caro-lina manufactures such as industrial management, computerapplications, plant engineering and material handling. Lim-ited technical assistance, information and site visits are pro-vided free of charge. More extensive support and consulting arepriced according to project length and required resources.

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N.C. Cooperative Extension ServiceN.C. State UniversityCollege of Agriculture and Life SciencesRaleigh, NC 27695Phone: (919) 515-3173Web site: http://www.ces.ncsu.eduThe Cooperative Extension Service can provide technicalassistance, publications and research about water efficientlandscaping. Also see your local county agents.

Waste Reduction Partners - WestLand-of-Sky Regional Council339 New Leicester HighwaySuite 140Asheville, NC 28806Phone: (828) 251-6622Web Site: http://www.landofsky.org/wrpWaste Reduction Partners - CentralTriangle J Council of Governments4307 Emperor Blvd., Suite 110Durham, NC 27703Phone: 919-558-2702Web site:http://www.tjcog.dst.nc.us/regplan/wastereduce.shtmlWaste Reduction Partners, a team of highly experiencedvolunteer engineers, architects and scientists, provides busi-nesses and industries with no-cost waste and energy reduc-tion assessments and technical assistance.

State Government OrganizationsN.C. Division of Pollution Prevention and Environ-mental Assistance(Technical and financial assistance to businesses, in-dustries and municipalities)1639 Mail Service CenterRaleigh, NC 27699-1639Phone: (800) 763-0136 or (919) 715-6500Web site: http://www.p2pays.org

N.C. Division of Water Resources(Water supply assistance, planning, allocation andconservation)1611 Mail Service CenterRaleigh, NC 27699-1611Phone: (919) 733-4064Web site: http://www.ncwater.org

N.C. Division of Water Quality(Water reuse permitting, wastewater permitting, taxcredits, concentration/mass-based wastewater permitissues)512 N. Salisbury StreetRaleigh, NC 27604Phone: (919) 807-6300Web site: http://h2o.enr.state.nc.us

N.C. State Energy Office(The Utilities Savings Initiative, Performance Con-tracting and financial assistance)N.C. Department of Commerce1340 Mail Service CenterRaleigh, NC 27699-1340Phone: (919) 733-2230Web Site: http://www.energync.net

National Water Efficiency ProgramsAmerican Water Works Association6666 West Quincy AvenueDenver, CO 80235Phone: (800) 926-7337Web site: http://www.awwa.orgThe American Water Works Association is an internationalnonprofit scientific and educational society dedicated tothe improvement of drinking water quality and supply.

N.C. American Water Works Association and WaterEnvironment Association3701 National Drive, Suite 205Raleigh NC 27612Phone: (919) 784-9030Web Site: http://www.ncsafewater.org

U.S. EPA’s WaterSense Partnership ProgramOffice of Wastewater Management (4204M)1200 Pennsylvania Avenue N.WWashington, D.C 20460Phone: (866) 987-7367Web site: http://www.epa.gov/watersenseWaterSense, a partnership program, seeks to protect thefuture of our nation’s water supply by promoting water effi-ciency by assisting consumers in identifying water-efficientproducts and programs.

Waterwiser6666 West Quincy AvenueDenver, CO 80235Phone: (800) 926-7337Web site: http://www.waterwiser.orgWaterwiser offers a comprehensive clearinghouse of resourceson water conservation, efficiency and demand managementfor conservation professionals and the larger water supplycommunity.

Irrigation Association6540 Arlington Blvd.Falls Church, VAPhone: (703) 536-7080Web site: http://www.irrigation.orgA WaterSense partner. Industry association provides BMPfor outdoor watering. International standards, advocatorand certifies irrigation professionals.

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Landscaping/Irrigation Associations

Other Water Resource InformationSustainable Office Tool KitGeorgia Dept. of Natural ResourcesWeb site: http://www.p2ad.org/toolkitThe Sustainable Office Toolkit is a set of resources and toolsdeveloped to help offices of all types and size move towardsustainability through practices such as recycling, energy andwater conservation and “green” building.

Toilet Information, testing and repairWeb site: http://www.toiletology.comThis Web site contains information on toilet care and re-pair including classroom-like lessons and how-to videos.

WATERGYU.S. Dept. of EnergyWeb site: http://www1.eere.energy.gov/femp/infor-mation/download_watergy.htmlWATERGY is a spreadsheet model that uses water/energyrelationship assumptions to analyze the potential of watersavings and associated energy savings.

Water Librarian’s home pageWeb site: http://www.interleaves.org/~rteeter/waterlib.htmlThe Water Librarians’ Web site provides links for dealingwith water and related topics; links to subject pages, librar-ies, publishers, collection development and current aware-ness sources.

Waste Reduction Resource CenterWeb site: http://wrrc.p2pays.orgThe Waste Reduction Resource Center provides pollution preven-tion technical support to the states in EPA Region IV. WRRC’sWeb site contains on online library, core references for many indus-trial sectors, vendor library and training courses.

VendorsUse local resources first. Many suppliers that a facility cur-rently uses may represent manufacturers of water efficientplumbing hardware, fixtures, controls, treatment and processequipment. Visit company Web sites for more information.

Auditing ToolsMicroWier Company LLC (503) 235-0792

Commercial Bathroom EfficiencyBradley Corporation (800) 272-3539Chicago Faucet Company (847) 803-5000Coyne & Delany Co. (434) 296-0166Kohler Plumbing (800) 456-4537Microphor Inc. (800) 358-8280Sloan Valve Company (800) 9-VALVE-9

Cooling Tower and Boiler Water Treatment and ControlMarley Cooling Towers (913) 664-7400Nalco Chemical Co. (630) 305-1000

Foodservice DishwashersChampion (877) 983-3663Hobart Corporation Representative (937) 332-3000

Foodservice PlumbingFisher Manufacturing Company (800) 421-6162Niagara Conservation (800) 831-8383T&S Brass and Bronze Works (800) 476-4103

General Domestic/PlumbingAmerican Standard Inc. (800) 442-1902Caroma (800) 605-4218 x88Crane Plumbing (800) 546-5476Delta Faucet Co. (800) 345-3358Eljer Plumbingware (800) 423-5537Elkay Manufacturing Co. (630) 572-3192Gerber Plumbing Fixtures Corp. (888) 648-6466Kohler (800) 456-4537Mansfield Plumbing Products (800) 999-1459Niboc Inc. (574) 295-3000Niagra Conservation (800) 831-8383Sloan Valve Co. (800) 580-7141Toto (888) 295-8134U.S. Brass Inc. (630) 629-9340Universal-Rundle (800) 741-3034Zurn Industries (800) 997-3876Plumbing vendor Web site:http://www.plumbingnet.com/listc.html

Irrigation Suppliers - N.C.John Deere Landscapes -http://www.johndeerelandscapes.comSmith Turf Irrigation - http://www.smithturf.com

American Society of Irrigation ConsultantsP.O Box 426Bryron, CA 94514-0426Phone: (925) 516-1124Web site: http://www.asic.org

Carolina Irrigation Association106 Main StreetBrookneal, VA 24528Phone: (800) 682-7774Web site: http://www.carolinasirr.org

N.C. Nursery & Landscape Association968 Trinity RoadRaleigh, NC 27604Phone: (919) 816-9119Web site: http://www.ncan.com

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Laundry Water ReuseGuestCare Inc. (301) 526-0922

Pressure Reducing ValvesAqua Saver (water saving devices for gravity toilets) (888) 328-2385Cash, A.W. Valve Mfg. (205) 775-8200Water Saving Toilet RetrofitsRectorseal Corp (Early Closing Flapper Valves) (800) 231-3354Watts Regulator Co. (978) 688-1811Wilkins (805) 238-7100

Pressurized Flush ToiletSloan Valve Flushmate (800) 533-3460

Spray NozzlesFOGG-IT Nozzle Co. (415) 665-1212Milton Industries Inc. (773) 235-9400Spraying Systems Co. (800) 95-SPRAY

Valve Shut-off (foot controlled)Pedal Valves Inc. (800) 431-3668T&S Brass and Bronze Works (800) 476-4103

Waterless Composting ToiletBio-Sun Systems Inc. (570) 537-2200

Vehicle Washing Water RecycleCalifornia Steam (800) 432-7999Custom Applied Technology Corp. (888) 536-7100Earth Care Technologies (479) 824-5511Kleer-Flo (800) 950-8020N/S Corp. (800) 782-1582Sioux Steam Cleaner Corp. (888) 763-8833Sobrite Technologies (309) 467-2335Specified Process Equipment Co. (707) 747-3466Waste Water Management Inc. (703) 846-0098

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