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7/28/2019 Storm Water Harvesting Guideline
1/16
HarvestingtHe potential
o stormwater
A guide for groups exploring stormwAter hArvesting
July 2008
Contents
Benets o stormwater harvesting 2
Step 1: Conrm suitability or stormwater harvesting 3
Water balance calculator 4
Step 2: Prepare a concept design 8
Step 3: Submit application and gain approvals 13
Step 4: Use stormwater responsibly 14
Potential stormwater project costs 15
Stormwater harvesting checklist 16
As part o Brisbane City Councils planto become a water smart city, Council isencouraging organisations and businesses toconsider all options to contribute to sustainablewater management. Harvesting the potential ostormwater has been developed by Council toguide the sustainable collection and sae reuse
o stormwater in Brisbane.
wh h?Stormwater is generated rom rainall, and includesruno rom hard suraces such as ootpaths, car parks,roads and natural suraces such as gardens and openspace. Although some stormwater soaks into the
ground, most stormwater in urban areas alls on hard orimpervious suraces and fows untreated via stormwaterdrains and pipes to local waterways and eventually intoMoreton Bay.
Stormwater harvesting reers to the collection andstorage o this runo or treatment and reuse at a latertime. This harvesting usually takes the orm o above-ground or below-ground storage to which water ispumped or diverted during periods o rain.
It is important that stormwater is managed eectivelyas it is a valuable alternative source o water where itsuse can also reduce the detrimental impacts that urban
developments can have on waterways.
H u h udStormwater harvesting can be a viable and cost eectivealternative to using town water or some uses. To helpdetermine whether it is the best option or your site andneeds, ollow the our-step process outlined in this guideto examine site suitability, design considerations, conceptdevelopment and the application process and how to usestormwater responsibly.
Checklists are also provided to help you ensure that allactors are considered in a logical order.
Also included are examples o local and national schemesthat have eectively implemented stormwater harvestingacilities using innovative techniques or capture, storage,treatment and reuse.
There are several instances where reerences or urtherinormation are provided. The stormwater harvestingweb page on Councils website also contains additional
inormation and can be used as a resource to support yourinormation search. Visit www.brisbane.qld.gov.au/wateror more inormation.
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Bf h
s d ub h
This guide provides comprehensive inormation toassist in determining your sites suitability or stormwaterharvesting, concept and detailed design requirements,and the application process. It also supports socially and
environmentally responsible use o harvested stormwater.The design and operation o stormwater harvestingsystems are the sole responsibility o the land owner. Theowner and operator must accept complete liability or allrisks and impacts associated with the system.
Beore working through the step-by-step process, it isimportant to understand the six overall outcomes thatstormwater harvesting projects need to consider to ensuresustainable use. These six key outcomes are applicableto all stormwater harvesting schemes and support thecompliance and regulatory requirements, as well asprinciples to guide eective design and implementation.
Key Outcomes o Stormwater Harvesting
Outcome 1 Stormwater harvesting protects publichealth and saety, and provides an alternative watersource t or compatible end uses.
Outcome 2 Stormwater harvesting reduces theimpact o stormwater pollutants on receiving waters(natural or articial).
Outcome 3 Stormwater harvesting protectsthe natural water cycle by enhancing andmanaging environmental fows and maintaining
in-stream habitat.Outcome 4 Stormwater harvesting maintainsoriginal food protection levels or urther mitigatesfood impacts.
Outcome 5 Stormwater harvesting supports localcommunity values and enhances public amenity andliestyle values.
Outcome 6 The total lie-cycle cost o stormwaterharvesting is comparable with alternatives orachieving all outcomes.
A orm o water recycling, stormwater harvestingrepresents a practical way to address some o our long-term water security problems, and to reduce the impactso urban development on waterway health.
The key benets o stormwater harvesting are two-old:
enhanced waterway management and an alternative watersource. These two benets complement each other.
Benets to our waterways
The amount o stormwater pollution generated rom asingle residential property is not high, but collectively thevolume o pollution that runs o urban areas is signicantand can harm our local waterways. Too much pollutedstormwater reaching waterways can cause disturbanceto aquatic habitats, increase bed and bank erosionleading to loss o vegetation, and increase the requencyo fash fooding.
Harvesting excessive amounts o urban stormwater canbe detrimental to waterway health. However, when abalance is maintained, stormwater harvesting improvesenvironmental health by:
re-establishingamorenaturalwatercycle
managing the requency and volume ostormwater runo and stream fow
protecting instream habitats and stabilising banks
reducingwaterwaypollution
the less polluted stormwater the lower the quantityo pollutants entering our waterways, the Brisbane
River and ultimately Moreton Bay pre-treatment processes can trap and lter
pollutants, reducing stormwater pollution reachingwaterways and groundwater.
Stormwater harvesting can improve the health oaquatic ecosystems.
Benets to our water supply
The demand on Brisbanes water supply is increasing inline with economic growth in industry and commerce, andcontinued population increases. Prior to water restrictionsbeing introduced, more than 50% o water used in SouthEast Queensland was or outdoor use. Stormwaterharvesting provides another alternative water source,particularly or large outdoor applications (includingirrigation o sports elds and parks) and other uses thatdont require drinking quality water (e.g. toilet fushing).
In addition to providing an alternative source o water, welldesigned stormwater harvesting systems can result in many
positive benefts such as improving stormwater quality, providinghabitat, creating recreational opportunities, improving visualamenity and providing educational opportunities.
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Step 1Confirm suitability forstormwater harvesting
Step 2Prepare a
concept design
Step 3Submit applicationand gain approvals
Step 4Use stormwater
responsibly
Stormwater harvesting can provide a sustainablealternative water source or organisations anddevelopments with the potential to capture or temporarilystore sucient volumes o water or use on their premises,and, or those with the capacity to regularly use largevolumes o water on their premises.
The groups most likely to benet rom exploring
stormwater harvesting include:
schools,universitiesandotherinstitutions
organisationswithlargesportingelds(e.g.footballelds, gol courses)
propertydevelopersoflargeurbandevelopments
businessandindustrywithhighwaterneedsofnon-drinking water quality.
Follow the inormation in Step 1 to better understand yoursites suitability or stormwater harvesting.
1.1 Determine i your site is suitableThe suitability o stormwater harvesting or irrigationis site-specic and depends on certain characteristicsincluding:
slope and drainage
The slope o the site should be assessed todetermine likelihood o runo and ponding. Ideallythe slope o the application area should be lessthan 15 degrees.
infltration and discharge rates
The composition o the soil (i.e. clay or sand) mayaect the rate o inltration and discharge. You canundertake a soil test to conrm the suitability oyour sites soil.
The depth o the water table below the site mayalso impact on the easibility o the stormwaterreuse scheme. You can undertake an assessment toestablish the depth to the water table.
land availability
Cost-eective stormwater harvesting schemes willbe located within close proximity to the preerredstormwater capture or harvesting point, and willhave sucient land area to hold any storage tanks,treatment units and distribution inrastructure suchas pipes and pumps.
vegetation
Stormwater harvesting schemes should be locatedin areas which do not require any removal ordisturbance o any terrestrial or waterway vegetation.
1.2 Prepare a water balance assessment
Unlike other alternative water sources such as recycled
wastewater or greywater, stormwater harvesting is runo-dependent. The viability o stormwater harvesting will bedependent on the level o security or reliability and volumeo water required. Use the Water balance calculatoronpage 4 to guide your assessment.
I rainall patterns are highly variable, and the intended useis reliant upon a consistent supply (e.g. irrigation needs totake place on a very regular basis), it is recommended thatstormwater harvesting be considered as a supplementarysupply, rather than the sole supply.
1.1 Determine i your site is suitable1.2 Prepare a water balance assessment1.3 Identiy the risks associated with using stormwater1.4 Investigate the likely costs o stormwater harvesting and unding options1.5 Review statutory requirements1.6 Talk to key stakeholders1.7 Proceed to the next step
s 1: Cf uby h
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ENVIRONMENT
WATERSUPPLY
Healthyecosystem
Waterefficiency
Demand/ Use
Watersupply
Mains (town) water
% megalitres
Stormwater harvesting
% megalitres
Total
% megalitres
Other (e.g. roofwater/greywater)
% megalitres
WATER SUPPLY
How much water doI need?What sources of watercan I potentially use?
Irrigation
megalitres
Water source
a) megalitres
b) megalitres
Total
megalitres
DEMAND / USE
What do I needwater for?How much water doI need for each use?
Other
megalitres
Water source
a) megalitres
b) megalitres
In this example, a more secure backup water supplyshould be available when demand cannot be met rom theharvested stormwater. For irrigation purposes, 60 to 80%reliability is usually sucient.
The most ecient stormwater harvesting projects typicallyhave a close match between the amount o water required(demand) and the total amount o water to be providedby stormwater (supply) or other sources. See the Waterbalance calculatorabove. Both o these actors need to beconsidered beore you look at how you will collect, store,treat and distribute the stormwater.
1.3 Identiy the risks associated withusing stormwater
All recycled water schemes, including stormwaterharvesting, need to be appropriately designed and
managed to minimise risks. With good design, appropriatemanagement and monitoring, potential public health,public saety and environmental hazards can be minimised.In general terms, the greater the exposure and potentialor public contact with the harvested stormwater (treatedand untreated), the greater and more comprehensive riskassessment is required.
Stormwater can contain a wide variety o pollutants,including biological (e.g. organic matter such as soiland sediment) and chemical contaminants (e.g. pesticides,heavy metals and hydrocarbons). Such hazards maypresent risks to the community and the natural
environment. The potential risks o each stormwaterharvesting project must be identied and assessedduring the projects planning phase. This will enableany potential risks to be managed during the projectsdesign, rather than being let to the operational phase o
a project, where the costs o eective mitigation may beconsiderably higher.
An important requirement o a stormwater harvestingsystem is that the operator accepts complete liabilityor all risks and impacts associated with the system.To ully understand the implications o this liability, acomprehensive risk assessment needs to be undertaken.Legal advice may also need to be sought or complex orlarge-scale projects.
Risks all into three main categories - public healthand community saety, environmental protection andoperations. Inormation on the types o risks associated
with each are listed below. More comprehensiveinormation relating to likely causes and potentialimpacts o these risks can be ound on Councilswebsite www.brisbane.qld.gov.au/water
pubc hh d cuy y k
Protection o public health must never be compromised.The health risks rom stormwater are generally lowerthan or treated efuent, however stormwater harvestingdoes carry some health risks which need to be managedappropriately, including:
stormwatercontamination(pathogens,inorganicand
organic chemicals)
Water balance calculator
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unsafestoragesandinfrastructure(e.g.openwaterstorages, embankment ailure, storage overfow)
waterstagnationovertime
breedingmosquitoesandothervectorpopulations.
Stormwater harvesting is a relatively new concept,however, rules and regulations or use are evolving asurther insights into best practice principles and risksare gained. The overarching principles that guide thesustainable use o stormwater (at the time o printing) are:
Theprotectionofpublicandenvironmentalhealthisparamount and should never be compromised.
Ongoingprotectionofpublicandenvironmentalhealthdepends o the implementation o a preventive riskmanagement approach.
Applicationofcontrolmeasuresandwaterqualityrequirements should be commensurate with the sourceo recycled water and the intended uses.
Existing legislation that governs water quality andwater recycling practices applies to all stormwater
harvesting scenarios. Visit Councils websitewww.brisbane.qld.gov.au/wateror links torelevant legislation and guidelines.
Environmental risks
Environmental risks rom a well-designed and operatedstormwater reuse scheme are generally low. Howeverthere are risks that require appropriate management andmonitoring including:
stormwatercontamination(fromnutrients,pesticides and oils)
maintenanceofenvironmentalow
(e.g. overextraction o stormwater)
lossofnaturalhabitatandvegetation.
To manage environmental risks, all stormwater harvestingsystems, independent o size and complexity, needadequate design, operation, monitoring and maintenance.
Operational risks
There are many operational considerations that will needto be actored in to ensure ecient and cost-eectivesystem management. You will need to think aboutmaintenance and system operation early in the process.Risks associated with operation and maintenance include:
potentialforfailureofstormwaterdiversionmechanismor pump system
equipmentdamagefromhighsedimentloads,build-up and clogging
increasesinmaintenancetimeandcostassociatedwithpoor system design and layout.
Ensure that you are aware o all approvals, standards andguidelines that are required to be met or inclusion in yourdetailed design and subsequent application.
C sudy
Bb Bc gd (Qd)
The Brisbane Botanic Gardens at Mt Coot-tha areQueenslands premier subtropical botanic gardens.These 52 hectare gardens are situated seven
kilometres rom the City and are a major touristattraction in Brisbane oering walking trails andschool and community education programs. Therecent drought conditions have presented signicantchallenges, with approximately 59 megalitres o waterrequired annually to keep the gardens alive and t orpublic enjoyment. The annual cost o having waterexternally sourced and trucked in is close to$0.5 million.
Brisbane City Council (as owners and operators othe gardens) undertook a easibility exercise anddetermined that the water catchment capacity o thegardens is 50 megalitres annually, which is almostsucient to meet the gardens required water demand.The existing onsite storage capacity o 12 megalitres(made up o a dam, our shallow ornamental pondsand eight water tanks) is insucient to service all o thegardens water needs.
Council developed a strategy that involved theimplementation o a stormwater harvesting acility, anda solar powered desalination plant. The stormwaterharvesting acility has the capacity to supplement thegardens water supply with 18 megalitres o water, andwill cost approximately $850,000 to build. Runo willbe captured in the pond, and will undergo several
stages o treatment: rstly being sedimentary andbio-ltration (natural process in storage pond) andultimately through ultra violet membrane technology.This will result in high-grade water suitable orirrigation o public gardens.
To ensure the reliability o water supply, Council is alsobuilding a solar powered desalination plant to treatbore water or irrigation purposes. The desalinatedwater will be pumped into the stormwater storagepond, supplementing the capacity by 10 megalitres owater annually.
This type o innovation is a rst in Brisbane, and is an
example o how stormwater harvesting can provide agreat alternative supply o water.
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1.4 Investigate the likely costs o harvestingstormwater and unding options
The most signicant costs associated with stormwaterharvesting usually relate to storage and the level otreatment required to achieve the desired water qualityand reliability necessary or the intended use. For thisreason, treated stormwater can have a higher unit costthan town water and other alternatives such as recycled
wastewater and rainwater tanks.
Stormwater harvesting can be nancially attractive whenall benets are combined, and current and uture costsareconsidered.Opportunitiesforcostsavingsfromastormwater harvesting scheme include:
reductioninvolumeofmainswaterusedandassociated metered water charge
watertransportcostsmayreducebyhavinganonsitewater supply
landdevelopercapitalcostsfortownwateruseandreplacement o inrastructure
securityofsupplyinlightofwaterrestrictionsinthe uture.
The table on page 15 is provided to help you to preparea preliminary cost estimate or your proposed stormwaterharvesting acility.
ud uc
To assist the implementation o water eciency projectsby community organisations, a number o grants programsare available rom Council, and the State and Federalgovernments. Further inormation on initiatives can beound by visiting the websites listed:
Brisbane City Councilwww.brisbane.qld.gov.au/water
Department o Natural Resources & Waterwww.environment.gov.au/water/programs
Department o Environment and Heritagewww.communitywatergrants.gov.au
Sport and Recreation, Queenslandwww.srq.qld.gov.au
Environmental Protection Agencywww.qld.gov.au/grants
1.5 Review statutory requirements
In assessing the suitability o the site, the statutoryrequirements should also be addressed. View table onpage 7 as a starting point.
1.6 Talk to key stakeholders
I you are not the landowner (i.e. you are a lessee ortenant), approval will be required to use the land orstormwater harvesting. This may apply to schools, sportingclubs and community organisations. I this applies to you,any applications or licences or development applicationsto Council or other regulating bodies (e.g. DNRW) willneed to be signed and submitted on your behal bythe landowner.
The landowner needs to be made aware o any newinrastructure (e.g. storage tanks) or modications toexisting inrastructure, and needs to be assured that allrisks will be appropriately managed by the lessee, tenantor uture land owner. Agreement also needs to be reachedon maintenance and system monitoring. There may also
be other key stakeholders you might wish to consultincluding local community groups, adjacent neighboursor product suppliers.
1.7 Proceed to the next step
I you eel condent that the project can address the issuesraised above and that stormwater harvesting is likely tobe a cost-eective way o sourcing an alternative watersupply and improving waterway health, proceed to Step 2:Prepare a concept design.
You may wish to use the table on page 15 as a checklistto conrm that you have covered each o the elements
discussed in this step.
I during the preliminary investigations, stormwaterharvesting does not appear to be the best solution oryour site, there are other ways to help improve waterwayhealth and to access alternative water sources.
There are many types o water recycling schemes inoperation across Australia. For example, the collectiono roo water in rainwater tanks is popular and easy toinstall. I larger volumes o water are still required (e.g.or irrigation o sports elds), you may need to consideralternate sources o water.
For more inormation on alternative water supplies, visitCouncils website www.brisbane.qld.gov.au/water
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Step 2Prepare a
concept design
Step 1Confirm suitability forstormwater harvesting
Step 3Submit applicationand gain approvals
Step 4Use stormwater
responsibly
2.1 Identiy key skills and expertise to help develop a concept design2.2 Plan how you will capture or collect stormwater2.3 Plan how you will store the collected stormwater2.4 Identiy the treatment requirements matched to the intended end use2.5 Investigate approvals and permits2.6 Seek endorsement o concept design2.7 Proceed to the next step
s 2: p cc d
2.1 Identiy key skills and expertise to helpdevelop a concept design
It is highly recommended that you engage the services osuitably qualied proessionals to support the preparationo the concept and detailed design or your project.Depending on the size and scale o the project, you
are likely to require support rom surveyors, engineers,ecologists, landscape architects and water quality experts.
A concept design is required to outline:
proposedstormwaterharvestingsiterelativetothecatchment / stormwater collection area (including anysite eatures such as waterways and drainage paths)and the location o dierent land uses in thecatchment area
sitecharacteristicssuchastheslopeofthesite,soiltype and permeability, services (such as electricity,telecommunications, sewage), surroundinginrastructure (such as ootpaths, carparks, gardens)
stormwatercollectionandstorageinfrastructure,including details o inrastructure such as pumps,pipes, tanks, their location and general conguration
processformovingwaterfromstoragetoendpointand preventing backfow (e.g. pumps, pipes andirrigation systems)
applicationareasforreusedstormwatersuchas sports elds to be irrigated (includingapproximate dimensions)
keyinfrastructureandprocessesformaintenance(such as access pits)
locationoflegalpointsofdischargeoroverowpoints keylandscapingfeatures.
The concept design should also be supported with yourwater balance assessment (that identies the varioussupply and demand requirements) and your initial riskassessment (that details how major identied risks willbe addressed).
Cc d
I your organisation leases land rom Brisbane City Council,you must provide your concept design to CouncilsLeasing Unit to obtain interim approval rom Council toproceed. The Leasing Unit can be contacted by phoning(07) 3403 8888.
2.2 Plan how you will capture orcollect stormwater
The majority o stormwater runo and overland fow isgenerated by requent, small-to-medium intensity rainevents, not rom the more inrequent and heavy prolongedrainall. It is thereore important that systems to capture
rainall rom smaller events are in place, as this can resultin harvesting a signicant portion o the total availableruno or reuse. Research suggests that aiming to capturethe rst 15mm o rainall will achieve optimal water supplyreliability and waterway heath benets. Hydrologicalmodels can assist you to calculate this or yourspecic project.
There are many innovative ways to capture or collectstormwater including:
redirectingtheowofwateroverlandtoasitesuitableor collection
extractingorpumpingandstoringstormwaterfor
later use
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capturingrainwatertankoverow,anddivertingoverland stormwater fow into above-ground or below-ground storages
accessingstormwaterfromclosedsystems(pipednetworks) and pumping the water to above-ground orbelow-ground storage tanks
accessingandpumpingwaterfromanundergroundaquier that is replenished with treated stormwater
(also known as aquier reuse and recovery, or managedaquier reuse).
Stormwater can be collected in the drainage network andthen be directed to an underground storage area.
2.3 Plan how you will store the collectedstormwater
When determining storage options, consideration mustbe given to potential impacts on the environment andpeople, as well as what statutory requirements mustbe met. The design o a stormwater storage is largely
dependent on the likely usage and demand or stormwater(i.e. the volume o water required and its requency ouse). The water balance assessment prepared in Step 1will assist with the storage design in terms o volumesand sizing.
There are several actors that infuence what type ostorage is most suitable to a particular site including:
volumeofwaterrequiredforusethiswillindicatewhether the demand and supply are balanced, orwhether a backup water supply is required to meettotal demand
amountofwaterthatcanbecapturedthis will infuence the size o storage required
storagedurationandthetimeframeforusingstormwater ollowing its collection
landavailabilityconsideravailablespaceassomestorage acilities require more space than others
publicsafetyopenstoragesareinvitingtochildrenand pets and may require encing and signage
publichealthstoredwaterthathaspotentialforhuman or animal contact must be treated to an
acceptable standard to avoid serious health issues
managementofwaterqualityinstoragefacility
designofstoragedevicestoexcludeinsectvectors,small mammals and birds, as interaction may pose risksto public health.
Collected and treated stormwater can be stored in above-ground tanks or below-ground reservoirs.
Some open water bodies such as this specifcally designedsedimentation basin and constructed wetland can also beused to store stormwater beore reuse.
Stormwater storages generally all into three categories:
below-groundtankorreservoirgenerallymadetodesign with concrete, or pre-manuactured purpose-built tank
above-groundclosedtankorreservoirgenerallythese are pre-manuactured and purpose built
above-groundopenstorageinaconstructedwetlandor ornamental water eature.
Closed storages (above or below-ground) such as tankssimilar to those used to collect and store rainwater arepreerred by Council to open storages and are easierand more cost-eective to maintain. I open storages areplanned, they should be designed using the principles or
constructed stormwater wetlands. These principles can beviewed at www.brisbane.qld.gov.au/water
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Regardless o the type o storage acility, stormwatershould be used within 24 hours. This short timerameallows or some ne sediment to settle out o the water,and avoids the potential or water to become rich innutrients and potentially harmul to the environment andgeneral public i discharged. Treatment o the harvestedstormwater prior to storage may be required i it isintended to store the water or any length o time beyond24 hours. Designs that include elements o Water Sensitive
Urban Design (WSUD) such as gross pollutant traps (GPTs),sediment basins, rain gardens (bioretention systems), orconstructed wetlands provide very eective pretreatmentand can be applied to suit various treatments levels.For more inormation on WSUD, visit the SEQ HealthyWaterways Partnership Water by Design web page atwww.healthywaterways.org/wbd_project_overview.html
Storage tip
Generally, the greater the level o nutrients and thehigher the temperature, the shorter the storage timeshould be.
All storages must have a legal point o discharge toensure that overfows are managed and any nuisance toneighbours (such as fooding and odour) is avoided.
2.4 Identiy the treatment requirementsmatched to the intended end use
The nal intended use is the key driver to determiningwhether harvested stormwater is a suitable alternativewater source. With appropriate treatment, stormwater haspotential to be used or a wide range o uses, includingirrigation o open spaces and sports elds, industrial uses,ornamental water eatures, and as a source o water oraquier storage or groundwater recharge.
Stormwater quality varies greatly between locations, andat dierent times it can be aected by rainall, adjacentconstruction activities, use o ertilisers, pesticides, septictanks, ageing sewerage systems and trac volumes in theupstream catchments. Even when obvious solid materialsuch as litter is removed rom the stormwater, dissolvedmaterial, biological (e.g. bacteria and viruses) and chemicalpollutants may still be present, but not visible. Careulconsideration must be given to the desired end use o anycaptured stormwater, and to the risk these contaminants
may have on the environment and public health.
Uses that are satised with lower water quality include thosewhere there is a low risk o contamination or exposure tohumans. The water must be appropriately treated to ensurethat the uses planned pose no risk to the environment orpublic health. The challenge to consider in doing this, isto ensure that you dont adversely aect the economicviability o stormwater harvesting by overtreating the wateror the chosen end use. This is why stormwater harvesting isparticularly well suited to low-quality end uses, as it reducesthe treatment and associated costs signicantly.
C sudy
Kh t squ (nsw)
Kogarah is a city o 50,000 residents, located 15kilometres south o Sydney. Its village-like centre,
Kogarah Town Square, has undergone a majorredevelopment which includes residential, retail andcommercial precincts.
A stormwater recycling acility has been establishedthat collects and treats rainwater and runo or reusein gardens, toilets and washing cars. The system hasbeen designed to capture 85% o rainwater alling onsite. This reduces the potable water demands o theSquare by 42%.
Following collection, stormwater is ltered via a grosspollutant trap, stored in underground storage tanksand ltered through sand and biologically engineered
soil. The system supplies all water or irrigation andabout 70% o the water used or toilet fushing.
Utilising captured stormwater runo to top-up roowater ensures a reliable alternative water supply.Further inormation can be ound by visitingwww.kogarah.nsw.gov.au
1 & 2. WSUD techniques such as natural channel designand constructed wetland systems provide excellentpretreatment o stormwater.3 & 4: Disinection through ultra violet treatment orchlorination will produce a very high quality water ft ormost end uses such as surace irrigation in public areas.
Treatment options
1 2
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Treatment tip
Essentially the greater the potential or human contactwith the water, the higher the level o water qualityrequired.
Using stormwater or residential purposes is technicallypossible, however, it may require the availability osignicant space or storage, and extensive and oten
cost-prohibitivelevelsoftreatment.Otheralternativessuch as roowater collection and treated greywater useare usually preerred.
t
Treatment options range rom basic to advanced,depending on the quality o stormwater captured andthe proposed end use. The ollowing table providessome preliminary inormation regarding treatment types.Experts must be consulted to ensure an appropriatelevel o treatment is incorporated in the design o thestormwater harvesting system. Basic and/or intermediate
treatment is suggested prior to storage and dependingon nal use, advanced treatment immediately beoreapplication or use.
s y d u
t y Quy ( ) p u
Bc(Level 3)
Remove litter andgross pollutants
3 Gross pollutanttrap, trash rack orscreen
Removes:
3 Leaves, litter and large materials
Does not remove:
7 Fine sediments, bacteria , dissolved
chemical contaminants and organicmaterials
Public access to water must be controlled
3 Controlled irrigation spray or drip irrigation subsurace irrigation o open spaces,
parks and sportsgrounds
3Industrial use dust suppression, construction site use
3 Ornamentalwaterbodies(with access controls)
id(Level 2)
3 Sand lters
3 Sedimentation(settling ponds)
3 Porous pavers
3 Bioretention
3 Constructedwetlands
Removes:
3 Sediments
3 Dirt, grit and some associated metals
3 Nutrients
3 Some pathogens
Does not remove:
7 All pathogens reduces levels butdoes not completely remove
y u
3 Irrigation spray or drip irrigation o open spaces,
parks and sports grounds
3 Industrial use dust suppression, construction site use,
process water
3 Ornamentalwaterfeatureswithhighchance o public contact
3 Fireghtingadcd(Level 1)
3 Membranetechnology
3 Electrolysis
3 Disinection chlorination,
UV or ozone
Removes:
3 All Level 2 and 3
3 Pathogens
u h h c ubc cc
3 Reticulated non-potable water garden watering toilet fushing car washing
3 4
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2.5 Investigate approvals and permits
Depending on the catchment area, the size andintended design o the stormwater harvesting schemeand associated inrastructure, a number o licences andapprovals rom Council and the State Government may berequired. Reer to Section 1.5 Statutory requirements as aguide only.
Regulations in relation to stormwater harvesting are
constantly evolving and changing. Many o thesechanges are outside the control o Council. It is stronglyrecommended that additional research and consultationbe undertaken with all relevant government regulators andstakeholders to ensure all relevant statutory requirementsare identied beore the concept design is nalised.
2.6 Seek endorsement o concept design
To ensure proposed stormwater harvesting projects meetCouncil expectations and address key issues, conceptdesign should be discussed early in the process with:
aCouncilDevelopmentAssessmentofcer,iftheproject is associated with a current developmentapplication
theCouncilLeasingUnit,iftheprojectislocatedonasite leased rom Brisbane City Council
anofcerfromCouncilsWaterResourcesforallotherprojects.
You should also discuss the concept with the land owner(i not Brisbane City Council).
2.7 Proceed to the next step
As discussed in this step, requirements dier dependingon the ownership o the site being considered orstormwater harvesting.
Leasehold land: I you lease land rom Brisbane CityCouncil or another government body, you must submityour concept design to Council or the relevant landowner or interim approval. You will receive noticationo interim approval once Council is satised that allstandards and risks have been addressed.
I your application was not approved, there aremany other water initiatives that may be worthconsidering. Visit www.brisbane.qld.gov.au orphone (07) 3403 8888 or more inormation on
Councils water saving strategies.
Private land: I you are a private landowner, ensure thatyou have addressed all o the elements in Step 2.
C sudy
Dckd pk, vc
Docklands is a waterront destination in Melbournewhich houses approximately 20,000 people. It is alsoa major tourist destination, with a signicant areadedicated to outdoor spaces.
Docklands Park, within the Docklands precinct, is anecologically sustainable parkland. The design o theparks stormwater collection and reuse system eaturesthree wetlands, which will capture and treat 90% o thestormwater generated rom the seven-hectare Grand
Plaza and Harbour Esplanade catchment area.
The captured stormwater is initially treated usingbiolters and the wetlands, and is urther renedthrough ultra violet treatment prior to use. Treatedstormwater is stored in sub-surace tanks or parkirrigation. Eighty percent o the parks annualirrigation requirements will ultimately be met romtreated stormwater, saving an estimated 10 millionlitres o Melbourne drinking water each year.Further inormation can be ound by visitingwww.docklands.com
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Step 3Submit applicationand gain approvals
Step 1Confirm suitability forstormwater harvesting
Step 2Prepare a
concept design
Step 4Use stormwater
responsibly
OnceyouhavecompletedSteps1and2,youcanstartthedetailed design and ormal application process.
3.1 Develop a detailed design o yourstormwater harvesting system
A detailed design o your stormwater harvesting systemwill be required to support a development application.This detailed design builds on the conceptual designdeveloped in Step 2. You will most likely require theservices and advice o qualied proessionals to assistin developing this. Phone Council on (07) 3403 8888 todiscuss your project with a Development Assessmentocer, who will conrm what you are required to submit.
The ollowing reerences may be useul in developing yourdetailed design.
Water Sensitive Urban Design Guidelines or SEQ(2006) developed by the SEQ Healthy WaterwaysPartnership. www.healthywaterways.org/wsud_technical_design_guidelines.html
Integrated Stormwater Treatment and Harvesting:Technical Guidance Report(2006) published by MonashUniversity. http://iswr.eng.monash.edu.au/research/
projects/stormwater Australian Runo Quality A guide to Water Sensitive
Urban Design Engineers Australia (2006).http://www.arq.org.au/
Managing Urban Stormwater Harvesting and Reuse(2006) published by NSW Dept o Environment andConservation. www.environment.nsw.gov.au/stormwater
National Water Quality Management Strategy:Australian Guidelines or Water Recycling: ManagingHealth and Environmental Risks (Phase 1, 2006and dratPhase 2, May 2008). Natural ResourceManagement Ministerial Council, Environment
Protection and Heritage Council and AustralianHealth Ministers Conerence. www.ephc.gov.au/ephc/water_recycling.html
3.2 Submit a development application
As in Step 2, the process or submitting a developmentapplication diers depending on the ownership o the sitebeing considered or stormwater harvesting.
Leasehold land: I you lease land rom Brisbane CityCouncil, you need to submit your nal detailed designpackage to Councils Leasing Unit. Council will signthe development application on behal o the lesseeand submit it to Councils Development AssessmentBranch. Even i you are not required to submit adevelopment application under Councils City Plan,stormwater harvesting applications need to be cited byCouncils Leasing Unit or sign o and approval beoreyou can commence with any works.
Private land: I you own the property, you can lodgeyour development application directly with Councilthrough the development assessment process (visitwww.brisbane.qld gov.au or more inormation).
3.3 Prepare nal work plans and sitemanagement plans
Final approval or simple stormwater projects not
requiring development approval rom Council mayonly take a couple o weeks or the nal project designto be approved. Negotiation o the Licence to AccessStormwater Inrastructure may take a little longer as thisis a legally binding document and may require additionalconsultation with legal representatives.
Timerames associated with the approval o morecomplex stormwater harvesting projects associated withdevelopment applications should be discussed with theprojects allocated Development Assessment ocer.
During this time, you may wish to consider thedevelopment / nalisation o work plans, construction
schedules and site management plans to ensure the siteand the stormwater harvesting scheme is managed saelyand sustainably.
3.1 Develop a detailed design o your stormwater harvesting system3.2 Submit a development application3.3 Prepare fnal work plans and site management plans
s 3: sub c d
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pjc c $
py d cc d
Geotechnical and soil survey
Engineering design
Landscape design and other design
Application ees
iucu d cucSite preparation and construction
Stormwater capture and collection
Storage acility
Treatment plant and systems
Distribution network and irrigation
Landscaping
mc d
Ongoingtreatmentcostsandreplacementparts
Inspections
Regular maintenance
Electricity
total
Potential stormwater project costs
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Brisbane City Council
Information
GPO B 1434
For more information
visit www.brisbane.qld.gov.au
ll (07) 3403 8888
printed onrecycled paper
s h chck
Step 1: Confrm suitability or stormwater harvesting
Determine i your site is suitable Prepare a water balance assessment Identiy the risks associated with using stormwater Investigate the likely costs o stormwater harvesting and unding options Review statutory requirements Talk to key stakeholders Proceed to the next step
Step 2: Prepare a concept design
Identiy key skills and expertise to help develop a concept design Plan how you will capture or collect stormwater Plan how you will store the collected stormwater Identiy the treatment requirements matched to the intended end use Investigate approvals and permits Seek endorsement o concept design Proceed to the next step
Step 3: Submit application and gain approvals
Develop a detailed design o your stormwater harvesting system Submit a development application Prepare nal work plans and site management plans
Step 4: Use stormwater responsibly
Prepare a risk management plan Understand your reporting and monitoring requirements Identiy opportunities or education and learning