town of eastham – integrated approach to nutrient management · human health need – public...
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Town of Eastham – Integrated Approach to Nutrient Management Jane Crowley, RS MS | Town of Eastham Anastasia Rudenko, PE ENV SP | GHD Jessica Janney | GHD
GHD @ NEWEA 2016
Presentation outline
• Community profile • Planning effort history • Human health need
– Public water supply • Environmental health needs
– Coastal estuaries – Freshwater Ponds
• Next steps
GHD @ NEWEA 2016
Community profile
• Seasonal community with 5,700 year-round residents – substantial increase in summer
• All properties are currently served by private drinking water wells and on-site septic systems
• Documented nutrient impacts to coastal waters and ponds
GHD @ NEWEA 2016
Planning effort history
Interim Needs Assessment Report and Alternatives Screening Analysis Report (March 2009)
Wastewater Management Planning Project Plan Evaluation Report
(June 2009)
Human health needs Environmental health needs
Public water supply Nauset-Town Cove Estuary – advanced
treatment
Rock Harbor Estuary re-classification and/or advanced treatment
Freshwater ponds treatment
2009 Planning Efforts
GHD @ NEWEA 2016
Planning effort history – evaluation findings
1. Town-wide municipal drinking water system from a protected source is needed – under implementation
2. Town-wide sewer system is not needed, but advanced wastewater treatment is needed for selected areas of Town – reevaluation based on updated MEP report and 208 Plan
3. Pond water quality problems are best solved by in-pond treatment – implemented for Herring Pond and Great Pond
GHD @ NEWEA 2016
Planning effort history – evaluation findings
1. Town-wide municipal drinking water system from a protected source is needed
2. Town-wide sewer system is not needed, but advanced wastewater treatment is needed for selected areas of Town
3. Pond water quality problems are best solved by in-pond treatment
GHD @ NEWEA 2016
Human Health Need
• Public Water System • $146,000,000 project
• Funded completely through the tax base
• Approved at Town meeting after several failed attempts
• Currently the largest infrastructure project on the Cape
GHD @ NEWEA 2016
Eastham Municipal Water Project Voter History Town Approval Requires both: • Funding Approval requires 2/3 majority support at Town Meeting • Majority approval at Ballot May 2007 System Failed to gain 2/3 support October 2007 System Failed to gain 2/3 support May 2009 Construction and permit supply well
sites approved May 2012 System Failed to gain 2/3 support May 2013 System Failed to gain 2/3 support May 2013 Approved at Ballot June 2013 System Failed to gain 2/3 support May 2014 Approved Phase 1 - Partial System ($40.8M) May 2015 Approved Town Wide System ($85M)
GHD @ NEWEA 2016
GHD @ NEWEA 2016
Human health need – public water supply
Drinking water impacts • On-Site Septic Systems • Impact of the Town landfill • Being addressed with the installation
of Town water system – Water transmission system being
installed – Initial phase of project underway,
properties will start being connected in Fall 2016
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Eastham Landfill Source of Contamination to Private Wells
• Closed Landfill approximately 10.4 acres directly across the street from single family homes
• In operation 1937 to mid 1990’s • Post Closure Groundwater monitoring as required by DEP lead to detection of
1,4 Dioxane that resulted in an Immediate Response Action Plan (IRA) first Detected November 2012
• 1.4 Dioxane is present in industrial sources and household products • Fully miscible in ground water • Infinitely soluble, moves in groundwater, not easily removed • Investigation ongoing to define the extent of migration… involved EPA, DEP
and Boston University • Likely to be carcinogenic • About 40 households currently receiving bottled water • More than 300 wells sampled
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1,4 Dioxane Detected
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Planning effort history – evaluation findings
1. Town-wide municipal drinking water system from a protected source is needed
2. Town-wide sewer system is not needed, but advanced wastewater treatment is needed for selected areas of Town
3. Pond water quality problems are best solved by in-pond treatment
GHD @ NEWEA 2016
Current planning efforts
• Completed Interim Needs Assessment Report and Interim Alternatives Screening Analysis Report in 2009
• New information since 2009: – Refined watershed delineations – New Massachusetts Estuaries Project (MEP) reports with estimated
removal %’s – Cape Cod Commission 208 Plan Update
• Wastewater management planning – Update Needs Assessment Report – Update Alternatives Screening Analysis Reports
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Environmental health need – coastal estuaries
2009 Current
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208 planning effort summary
• Cape Cod Commission has submitted Section 208 Cape Cod area-wide water quality management plan update (208 Plan Update) signed by Governor Baker in June 2015
• Submitted to EPA • EPA Approved September 2015
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208 planning tools – Watershed MVP
• CCC Tracker Model – Estimates quantities (linear ft, areas,
number of properties serviced, number of systems etc.) of different technologies to meet a nutrient mitigation goal
– Quantities can be input into 208 Map viewer to determine proposed locations for the technologies
– Further studies would be needed to determine optimal locations for these technologies based on variables not included in the 208 Map Viewer (such as site suitability and public acceptance).
GHD @ NEWEA 2016
Current planning efforts (continued)
• Public outreach – Presentations at public meetings – Workshops – Newsletter on project
• Evaluations – Development of hybrid approaches (combination of traditional and non-
traditional approaches) for two targeted watersheds • Continued coordination with MassDEP, Cape Cod Commission, and
neighboring towns • Look for piloting and project opportunities
GHD @ NEWEA 2016
Planning effort history – evaluation findings
1. Town-wide municipal drinking water system from a protected source is needed
2. Town-wide sewer system is not needed, but advanced wastewater treatment is needed for selected areas of Town
3. Pond water quality problems are best solved by in-pond treatment
GHD @ NEWEA 2016
Environmental health need – freshwater ponds
Eastham Ponds Action Plan • Included 11 kettle ponds • Community concerns regarding deteriorating
conditions • Loss of water clarity, algal blooms, odors,
excessive weeds affecting recreation, changes in fish community
• Pond Action Plan was a recommended action of the Eastham Wastewater Management Plan
• PAP completed in 2011, ongoing implementation and assessment
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Phosphorus levels are key to pond health
Total phosphorus Attributes Fisheries and recreation 6 – 12 ppb Clear water, well oxygenated Cold water fishery
12 – 24 ppb Shallow lakes may become anoxic, water moderately clear
Transitional fishery
24 – 96 ppb Deep water anoxia Diminished clarity More plants
Less suitable for contact recreation, warm water fishery
96 – 192 ppb Persistent algal blooms Anoxia
Unattractive for recreation Harmful algal blooms Fish kills possible
Great Pond Herring Pond (252) Water Clarity
Cape Cod Commission criteria for “healthy ponds”
GHD @ NEWEA 2016
GHD @ NEWEA 2016
Objective
• Find effective strategies to protect and restore kettle ponds for their desired uses – now and in the future
• Develop specific, targeted recommendations for community consideration
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Summary of remedial measures
Technique Suitability Description
Alum treatment program
Stratified lakes, excessive algae, internal P a major component of budget, iron-rich sediments
Application of alum to prevent soluble P release from sediments during anoxic conditions
Enhanced circulation
Small ponds with transient DO depletion, excessive algae
Whole lake circulation to eliminate anoxia in lower waters where sediment recycling of P occurs
Watershed BMPs Ponds affected by development
Stormwater management, septic discharge setbacks, public education, land acquisition
Dredging (nearshore areas)
Ponds impaired by loss of depth, emergent vegetation
Removal of sediment and vegetation from pond bottom.
GHD @ NEWEA 2016
Pond ranking
Criteria used Science-based • Extent of use impairment
- Swimmable/fishable Policy Considerations • Ownership/public access • Size of pond • Prior treatment
Pond Priority Bridge Low
Depot Medium
Little Depot Medium
Great High
Herring High
Jemima Medium
Minister High
Molls Low
Muddy Medium
Schoolhouse High
Widow Harding Low
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Alum effectiveness – deep ponds
• Most effective on: • Ponds with significant internal phosphorus loading from sediments • Ponds that undergo stable thermal stratification and seasonal anoxia
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Alum Treatment
• Collect sediment samples from pond • Assay the sediments and calculate
application rate to immobilize iron-bound P in the pond’s sediments
• Apply calibrated mixture of aluminum
sulfate (alum) and sodium aluminate based on site-specific dose calculation
• Permit requires four quarterly sampling events following chemical treatment
GHD @ NEWEA 2016
GHD @ NEWEA 2016
Phosphorus content – Herring Pond
Alum treatment
0 20 40 60 80
100 120
Oct
-12
Dec
-12
Feb-
13
Apr
-13
Jun-
13
Aug
-13
Oct
-13
Dec
-13
Feb-
14
Apr
-14
Jun-
14
Aug
-14
Oct
-14
Dec
-14
Feb-
15
Apr
-15
Jun-
15
Aug
-15
Oct
-15
Dec
-15 Vo
lum
e-w
eigh
ted
P C
once
ntra
tion
(ppb
)
Date
Volume-weighted P Concentration (ppb)
Volume-weighted P Concentration (ppb)
GHD @ NEWEA 2016
Water clarity improvement – Herring Pond
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
2007 2008 2009 2010 2011 2012 2013 2014
Sum
mer
Sec
chi d
isk
tran
spar
eny,
m
Alum treatment
GHD @ NEWEA 2016
Great pond results
• Measure to protect water quality against deterioration
• Less dramatic than Herring Pond • Internal phosphorus mass reduced by
about one-half • Summer water clarity improved
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Next challenge – shallow ponds
• Fewer tools available • Alum possible, but effects are less
dramatic; requires multiple applications
• Enhanced mixing • Monitor and control invasive species
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Next steps
• Shallow pond remediation • Hybrid evaluations for coastal estuaries
CCC watershed reports and permits by June 2016
Environmental monitoring and adaptive management
Targeted Watershed Management Plans
(TWMPs)
Comprehensive Wastewater Management Plan (CWMP) –
MEPA Review Process
Continue Wastewater Planning Services (2015) Current Project
GHD @ NEWEA 2016
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