Eastham Water System Water Supply Development Program Board of Selectmen Update April 9, 2012

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Eastham Water System Water Supply Development Program Board of Selectmen Update April 9, 2012. Agenda. Why water? Benefits of a water system Water quality studies documenting conditions Relationship with wastewater planning Water supply investigations Water system preliminary design - PowerPoint PPT Presentation

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Eastham Water SystemWater Supply Development

Program

Board of Selectmen Update

April 9, 2012

Why water? Benefits of a water system Water quality studies documenting

conditions Relationship with wastewater planning Water supply investigations Water system preliminary design Cost forecasting and allocation

2

Agenda

Drinking water wells in close proximity to septic systems

Water quality is steadily declining from septic system cross-contamination

Documented in several studies No official water quality monitoring,

management program for private wells

Why Water?

Provide clean, potable water from protected and managed sources remote from septic systems, and other activities that can impact private well water quality

Strict EPA/DEP quality monitoring program Provide Town-wide Fire Protection Reduce Home-owners Insurance Costs by

$400-$500/year for Average Home

Why Water?

Long-term community investment in infrastructure

Water System Immune to Power Outage as happened in August 2011

You’ll know what you’re drinking Regular testing under strict guidelines Annual public reporting

Why Water?

Sign at Town Hall after August 2011 storm

Nitrates are a risk factor for infants, but are also an indicator

Larger concern: other wastewater components

Not normally tested for, are expensive, but are often present along with nitrates

Why Should We Be Concerned?

Nitrate

c

Downgradient well

Leach field

Household Products

Pharmaceuticals

Drinking wells intercepting plume at different distances from plume source and therefore showing different concentrations of nitrate

Projected Use of Innovative/Alternative On-site Sewage Treatment Systems in Eastham, Under Current Regulations and Policies

Susan RaskBarnstable County Department of Health and

Environment

2007

Bedroom density and nitrate levels

“Short circuiting” is occurring due to small lot size and large number of wells and septic systems;

“45% of lots exceed 4 BR’s/Acre model”

High number of samples > 2mg/L validates that entire groundwater system is showing nitrogen impacts from septic systems – not likely to improve

Bedroom density and nitrate levels

70% of single family residences (7 out of 10 homes) exceed the Title 5 standard for density on nitrogen sensitive lots – Eastham 2012

9,600 private wells tested since 2003 Approximately 1,000 per year Test only for Nitrates as low-$$ indicator Data analyzed by geographic map areas Clear geographic variability

North Eastham most severe South Eastham least severe

Eastham BOH Well Testing Program

% of Wells > 5 ppm Nitrates

Red > 30%Orange 20 – 30%Yellow 10 – 20%Green 0 – 10%Remember: Nitrates are an indicator

of other septic systemcompounds.

Principal Conclusions

“The Town needs to protect the public health by providing a reliable public water supply from a protected source.”

Eastham Wastewater Mgmt PlanGHD Inc., 2009

Wastewater Mgmt PlanGHD, Inc.

• Nearly all properties served by a well and septic system on the same lot

• Private wells are becoming impacted by septic tank effluent

• Contamination is indicated by elevated nitrate

• Protect public health with a public water supply

“Wastewater treatment alone will not remediate the existing human health need of safe drinking water.”

Wastewater Mgmt PlanGHD, Inc.

Wastewater Mgmt PlanGHD, Inc.

Sewer Service Areas• Not a Town-wide system

• Targeted embayments• Town Cove/Nauset

Estuary• Rock Harbor

Wastewater Mgmt PlanGHD, Inc.

Sewer Locations

Wastewater Mgmt PlanGHD, Inc.

Limited WW SystemCost estimate:$59 Million

Wastewater Mgmt PlanGHD, Inc.

“The human health wastewater needs are very clear and are best met with the development of a public water supply system from a protected water source.”

Sampled private wells across the Cape Tested for “Emerging Contaminants” from

septic systemsPharmaceuticals Cleaning SolutionsFlame retardants HormonesMetals Insect RepellentsPersonal Care Products

Possible health effects, unregulated, untested

2011 Silent Spring Institute Study

“Emerging Contaminants In Cape Cod Private Drinking Water Wells – 2011”

27 different contaminants detected More nitrate = more contaminants

= higher concentrations 3 pharmaceuticals at highest levels in the U.S. There are no standards for these

contaminants Consider home filtration if nitrate >0.5 ppm Did not test for bacteria and viruses

Silent Spring Study: Findings

Provide clean, potable water from protected and managed sources remote from septic systems

Provide Town-wide Fire Protection Reduce Home-owners Insurance Costs

by $400 - $500/year for Average Home Water System Immune to Power

Outage as Happened in August 2011

Why Water?

FY 2010 Annual Town Meeting, Article 17 Conduct pump tests to establish the

quantity and quality of water available from…Districts G, H and Nauset Regional High School and perform permitting necessary to provide up to 1 MGD from each site.

Evaluate feasibility of obtaining 0.5 MGD or more water from Orleans

32

Water Supply Investigation Program

GOAL

Town-wide Water

System

6667 Lots Served

Annual average day 1.00 MGD Summer average day 1.88 MGDPeak Day

2.65 MGD

.

Supply Sources

NRHS

District G

District H

Well Development

Approximate Salt Water Interface

N

NW: Sand to ~100’; silt/clay to 400’+SW: Sand to 400’; silt and clay layers

District G

District H

NRHS

Geology: Glacial Deposits

9

Nauset Lens

Groundwater Model

Groundwater Modeling of Potential Water Supply Withdrawals

Ground Water ModelingWater Supply Goal

Long-term effects on aquifer conditions

100-year period modeled Use annual average demand (1.0

MGD) Represents average demand at full

build-out of system

NRHS Site

0.882 MGD

NRHS Survey Map

District G

0.995 MGD

District H

1.30 MGD

District H

Town of Eastham

NPS

NPS

04/21/23 48McLane Environmental, LLCMcLane Environmental, LLCDRAFT

VP-09

OW-1A,B,C,DTPW-1B

OW-2A,B,C,DTPW-2C

OW-3A,B,C,TPW-3B

OW-4 A,B,C

VP-01

VP-11

District H – Surveyed Site Plan

Aquitard (Silty clay and silt / Silty sand )

Aquifer (Fine to medium sand with traces of coarser sand and gravel) 49

Northwest Southeast

A

D

B

C

Aquitard

Aquitard

Aquitard

Till or weathered bedrock

Gamma (cps)

8, 16, 32 Inch Normal Resistivity (ohm-m)

EM Conductivity (m/Sm)

Ele

vati

on

(ft

NA

VD

88)

Distance (ft)

McLane Environmental, LLC

Water Table- May 2, 2011

District H – Site Stratigraphy

Groundwater and Vernal Pool Monitoring

Monitor water levels in surface water, peat, and water table

Monitor three nearest vernal pools VP-01, VP-09 and VP-11

VP-9 and OW-4 Well Cluster

Vernal Pool VP-09

Orleans as a water supply?

Eastham can be entirely self-sufficient

Not enough available from Orleans to meet Eastham’s demands

Far less costly for Eastham to supply its own water

Interconnection for emergencies

Water System

Preliminary Design.

Phase 1

• Wellfields

• Transmission Mains

• Storage Tanks

• 1,391 Connections

Phase 1Fire Protection

•1000’ radius from mains

•Lower insurance rates

•Encompasses 75% of all lots

Fire Protection and Home Insurance Applies to all properties w/in 1000’ of system

and 5 miles of fire station

Wellfleet experience

ISO Rating dropped from Category 9 to 4

Reduced insurance for $400,000 home by $500 - $700/year

Projected insurance decrease for Eastham: $400 - $500/yr (for $400,000 home)

Phase 21126 Connections

95% fire protection

Phase 3

1117 Connections

Phase 4

1079 Connections

Phase 5

1502 Connections

Phase 6Seashore Area

284 Connections

Service Connections Program

System Cost

$111,000 construction cost(includes inflation through construction)

Construction in six phasesStarting 2015Two years each

Financing done in two-year increments

Cost Allocation Approaches

Taxes

Betterments

Connection Fees

Betterment Program

Every lot assessed based on value

Start-up betterment Final betterment

Betterment Program

Borrowing Period 20 yrsInterest Rate 2% - 4%Betterment Payback 20 yrs

Pursue grants and low-interest loans (SRF, USDA) and abatements

Financing the System

Low Interest Loans or Conventional Loans/ Grants

Betterment

Financing

$17,000 for 20 years at 2% (for average property at $400,000)

Average annual betterment: $400-$600/year

Homeowners insurance savings: $400 - $500/year

Water fees (if connected): $200/year Abatement program

Discussion

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