Impacts of Increased RunoffLocalized floodingChanges flood plain in larger streamsChanges stream channels (deepens, widens, steeper banks)

Impaired Streams

Caveats

Annual averages, not models for local or site-specific water supply or well analysesConundrum–larger areas allow more accurate but less useful estimates; estimates for small areas not really reliable for regulatory workNeed to refine results for watersheds and subwatershed (local uses) – data limitsBudgets based on issue – drought, average times, wet periods

What is Available Water?

Surface WaterSafe yieldDrought of recordSustainable demandsNo harm to othersNo harm to streamsBased on storage and stream flow

Ground WaterDependable yieldNo harm to aquiferNo harm to othersNo harm to streamsBased on recharge and well locations

The Major Public Users (Raritan)

Surface WaterElizabethtown WaterMiddlesex WaterNew BrunswickNorth BrunswickUnited Water-MatchaponixSayreville

Ground WaterElizabethtown WaterPerth AmboyNJ American WaterMany municipalities

Why Public Supplies?

Population density exceeds levels that on-site wells can supportCost-effectivenessLink to public sewer systemsSurface supplies – 1.2 million people

Passing Flows

Control withdrawals and/or releases to minimize low flow conditionsApplies to regulated withdrawalsMajor Raritan Basin controls

South Branch at Stanton StationRaritan at ManvilleRaritan at Bound Brook

Total Available Water

Surface WaterNJWSA 225 MGDNew Brunswick 8 MGDOthers – limitedConstructed facilities

Ground Water85-135 MGD totalAmount uncertainNaturally availableNot concentrated

Projected Water DemandsRaritan River Basin Water Supply Demands

225

250

275

300

325

350

1990 2000 2010 2020 2030 2040

Year

MG

D

Low Projections High Projections

Includes demands from out of basin

Assessment

Basin demand approaching available supplies before 2040 – new surface water project neededGround water demands can exceed local supplies in shorter times – proved by dry domestic wells in droughtMinimal additional ground water

Statewide Water Supply Plan

RecommendationsConservationProtect existing sourcesKingston Quarry if available in timeConfluence Pumping Station second bestSix Mile Run – wait

CaveatsPollution – can reduce availabilityGround water – demands must be spread to avoid overdrawing local aquifersGround water – estimates are roughConservation – use rates can changePassing flows – influence safe yieldsHydrology – development can change itClimate – changes affect yields

NJDEP Water Budget Project

Focusing on watersheds (HUC-11)Documenting site and size of all permitted water withdrawalsEstimating ground water rechargeEstimating flow needs (volume and timing) for aquatic ecosystemsDeveloping water budgets in 2004

Key Issues for Hunterdon County

Rely on local resources or import? Scale?Surface water or ground water?If ground water, how conservatively should supplies be estimated?What level of knowledge is sufficient?What roles for conservation, recycling and reuse of water?What level of aquatic ecosystem protection?What are the implications for master plans?