Rockland County Water: Alternatives for Supplying Demand

Sally HaasLAI531

April 18, 2010

Rockland County

Hudson River

Population: 298,545Number of Housing Units:

99,324Land Area: 174.22 square

miles

Rockland Water SupplyRockland County Water

Supply SourcesUnited Water NY 90% Small Water Companies 7% Private Wells (6,000 - 8,000)

3%

United Water NY Water Supply Sources

Lake DeForest 37% Alluvial well fields (includes

Ramapo and Mahwah Valley well fields) 31%

Bedrock wells 32%

Lake DeForest

Groundwater supplies 61% percent of the drinking water to Rockland County. This come from wells located in the southern 2/3rds of the county

Surface water supplies 39% percent of the drinking water to Rockland County including Lake DeForest, the Hackensack River and the Mahwah River.

Water Supply

Peak Supply is the volume available over a few daysRockland County peak supply capacity is 44.5MGD

(million gallons per day) with an additional 3MGD possible2006 Average sustainable supply was 32-34MGDFactors limiting supply:

Close spacing of production wellsNYSDEC limit allocation permitsDe Forest Lake withdrawal limits and treatment

capacityPeriods of low precipitationDevelopment (sewage treatment and storm drainage)

decreases recharge

Supply and Demand2006 Average sustainable supply 32-34MGD

Peak supply 44.5 MGD with 3 MGD availableActual average daily demand for 2005 was

31.06 MGD2010 estimated daily demand- over 33 MGD

with summer peak of 49MGD.

Supply Demand0

20

40 33 31

Other Potential Sources of Water

A new reservoir at Ambrey PondDesalination of brackish Hudson River

waterAdditional groundwater suppliesReuse of wastewaterIncreased use of Lake DeForestUse of the Suffern Quarry.

Short-term ProjectsUpdate Letchworth Water Treatment Plant- 2MGDSparkill Well Field Clean-up- 0.5 MGDNew wells from purchase of existing private wells-

1-1.5 MGDDivert water from Potake Pond to Ramapo River to

maintain levels in dry conditionsStore Lake DeForest spill during wet conditionsReservoir at Ambry Pond-NYS has not permitted

new damnDivert flood waters from Ramapo River to Suffern

Quarry-not pursued.

Conservation MeasuresLimiting Demand by Conservation is

desirableCan’t be counted onCan’t be legislatedLimiting development-non adherencePersonal efforts

Fix leaksLow volume toilets and restrictive shower

headsLow capacity washer and dishwasherLimit use-turn off faucets

Desalinate Hudson River WaterIn September 2007 United Water submitted a

proposal to build a pilot desalinating plant to be built in Haverstraw, NY.

The Salinity Gradient

Mile 0 26,000

Mile 255180

Mile 401600

Mile 5580

The table on the right shows salinity data in parts per million (ppm) for various points along the river measured on Oct 12, 2006.

4 Points and their salinities are illustrated on the map.Haverstraw is marked.100 ppm is considered drinkable.

X

Factors Affecting the SalinitySalinity fluctuates with the tidal cycle; peaking with high tide, dropping at low tide

Data from Beczak Environmental, Yonkers, NY; River Mile 18

PrecipitationRainfall has a strong and delayed affect on salinity

0

10

20

30

40

50

60

70

80

Salt

Fro

nt (

RM

)

•The location of the Salt Front (salinity 100 ppm ) in Mar-Apr and Aug-Sept measured by the US Geological Survey shows seasonal variation in the location of the Salt Front.

•Salinity of 100 ppm is considered drinkable•Rockland County is located between RM 23 to 45.

Desalination

Click to play video on how desalination works

Bear with the commercial and manually return to the presentation when you are finished.

Using a process similar to dialysis, water is forced through a fine membrane leaving the salts and other impurities behind

Costs for Reverse Osmosis Desalinator

Capital costsMembrane lifeEnergy for desalination processChemicals treatments through out the

processDistribution

Packaging and transportationOr infrastructure

Waste disposal

The proposed plant will cost between $80 and $100 million

Energy consumption:4427-6520 kilowatt hr/million gal.Compared with 250-3500 kWh/Mg for traditional

treatment facilitiesEstimated initial production 1.5 mgdNeed distribution to existing infrastructureWaste to be processed through the Joint Regional

Sewage Treatment facilityBased on video There is 30% recovery of intake. The

rest is processed as waste.

Haverstraw Project

Haverstraw SiteThe proposed site in Haverstraw is unused land owned by

US Gypsum (produce wallboard and construction products)Located across from Indian Point Nuclear Power Plant

Potentially radioactive contaminants not removed by desalinator

Towns of Ramapo and Stony Point have passed resolutions opposing desalination facility due to proximity to Indian Point and costs.

Not likely to run full-time only during low tide-related low salinityMore efficient, more costly not running at capacityNo mention of renewable energy sources like solar or wind

Some high salt waste water will backwash into the Hudson bringing other concentrated contaminants (PCBs)

Working Desalinators Worldwide Majority and largest are in the Middle East and

North AfricaThe largest is in Israel Evaporation or distillation most common method

There are 18 in the USCalifornia, Texas, Arizona, and FloridaReverse Osmosis most commonFebruary 2010: Solar panals for Swansea, MA plant

to provide 1/6th-1/4th of energy Australia is the only one using energy from a

renewable source

Benefits of DesalinatorOn December 14, 2006, the New York Public

Service Commission granted United Water New York permission to raise its rates for three years in a row, starting with a 23% hike in 2007.

UWNY charged with plan for sustainable solution resulting in proposal for Haverstraw desalinator in January 2007.

Benefits cited over developing reservoir at Ambrey Pond include: drought tolerance; perceived dam safety concerns from local neighbors; plant expandability; permitting requirements; complexity of construction; and cost.

ImpressionsNeed to increase supply

Desalinator to supply 2 MGD by 2015 increasing in phases to 7 MGD

Current peak demand is 49 MGDAre there other alternatives that have not been

considered or have been prematurely discounted? Withdraw further up river closer to salt front Ambry pond and Suffern Quarry

Future for DesalinatorTechnology should be developedImprovements to decrease costsSustainable energyWaste utilization

Water Policy and the PublicUnited Water has filed the proposal with the

StateA number of Town Hall Meeting are to be

ScheduledJanuary 12, 2010—No follow-up reportsApril 22, 2010—Public Hearing on Proposed

(21%) Rate HikeCitizen Action Groups: Sustainable Rockland

Includes: Sierra Club and Food and Waterwatch

Resolutions Opposing Desalinator ProjectTowns of Stony Point and Ramapo

Company files plan with new york state public service commission Retrieved 4/19/2010, 2010, from http://haverstrawwatersupplyproject.com/the-news/3-newsflash-2.html Haverstraw water treatment plant - water technology Retrieved 4/19/2010, 2010, from http://www.water-technology.net/projects/haverstraw-treatment/ Hudson river desalination - citizens campaign for the environment Retrieved 4/19/2010, 2010, from http://www.citizenscampaign.org/campaigns/hudson-river-desalination.asp Is the hudson too salty to drink? data puzzle number 4. Retrieved April 18, 2010 New york state | map-NY Retrieved 4/19/2010, 2010, from http://www.nysegov.com/map-NY.cfm?gameMode=on Swansea's desalination plant going green - taunton, MA - the taunton gazette Retrieved 4/19/2010, 2010, from http://www.tauntongazette.com/news/business_news/x1468647563/Swanseas-desalination-plant-going-green United water new York’s proposed desalination plant | riverkeeper Retrieved 4/19/2010, 2010, from http://www.riverkeeper.org/campaigns/river-ecology/waterfront-development-review/united-water-desal/ United water sites long-term water supply project in town of haverstraw Retrieved 4/19/2010, 2010, from http://haverstrawwatersupplyproject.com/the-news/4-united-water-sites-long-term-water-supply-project-in-town-of-haverstraw.html Vanderhoef, S.State of the county address. Retrieved 04/18, 2010, from http://www.co.rockland.ny.us/Executive/Documents/ExecAddress2010.pdf Water supply - desalination Retrieved 4/19/2010, 2010, from http://superfund.ciesin.columbia.edu/Rocklandwater/supply_desal.html Water supply - planning Retrieved 4/19/2010, 2010, from http://superfund.ciesin.columbia.edu/Rocklandwater/supply_planning.html Water supply - planning Retrieved 4/19/2010, 2010, from http://superfund.ciesin.columbia.edu/Rocklandwater/supply_planning.html#shortterm

References