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Preserving Our Water Resources: New Directions in Water Supply Planning. Office of Surface and Ground Water Supply. Ground Water Characterization Ground Water Withdrawal Permitting Wellhead Protection Ground Water Protection Steering Committee Surface Water Withdrawal Permitting
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Preserving Our Water Resources: New Directions in Water Supply Planning
Office of Surface and Ground Water Supply • Ground Water Characterization • Ground Water Withdrawal Permitting • Wellhead Protection • Ground Water Protection Steering Committee • Surface Water Withdrawal Permitting • State-wide Water Withdrawal Reporting • Local and Regional Water Supply Planning • Surface and Ground Water Monitoring • State Drought Monitoring and Response • Interstate Water Commissions
Cooperative Monitoring • Monitor water resources with USGS: 189 surface water, 422 groundwater, and 62 Total Maximum Daily Load (TMDL) data sites • 50/50 surface water, 80/20 groundwater • Help fund USGS real-time database. • www.water.usgs.gov
2010 Water Use Groundwater Use by Category = 178 MGD Surface Water Use by Category = 1,086 MGD
VA Water Quantity Mgmt Tools • Manage water withdrawals and use through regulatory programs: • Virginia Water Protection Program, • Ground Water Management Act of 1992, • Local and Regional Water Supply Planning Program • Water Use Reporting Program • Other tools like: • Potomac Low Flow Allocation Agreement
SW Availability Problems • Only 10% of existing withdrawals are under permits. • Most new or expanded water supply will require creation or expansion of storage. • Determining water availability is uncertain because the needs of recreation, navigation, and fish and wildlife habitat are not adequately defined • We are inefficient: 65% of public use is for outdoor watering and toilet flushing. • We forgot how to play nice in the sandbox…
GW Management Areas • Covers about 2/3 of the Coastal Plain • Regulates an estimated 57% of withdrawals >300,000 gpm in CP • Does not include most single family wells (est. 40 mgd)
VA Coastal Plain Aquifer Cross-Section McFarland & Bruce, 2006
Simulated water levels at top of Potomac aquifer. Potomac Aquifer Simulated Transient Water Level Elevations 2008 -70 -80 -90 -100 Results of transient simulation using actual reported and estimated withdrawals, 1900—2008
RASA Model Simulated Water Levels VCP Model Simulated Water Levels Top of Potomac Aquifer 2005 Total Permitted Withdrawal Steady-State Simulation
Simulated Change in Storage of Water in the Potomac Aquifer from Pre-development to 2008 Values >1 indicate head is below the 80% criterion
Pre-Development Flow ~ Potomac Aquifer CRATER 0 FT 140 FT
Post-Development Flow (2003) ~ Potomac Aquifer -180 FT CRATER 0 FT -180 FT
Saltwater Intrusion - Water Quality Changes McFarland, 2010, USGS Professional Paper 1772
Land Subsidence – Relative Sea-Level Rise Rates of Elevation Change (1940-1971) mm/year Holdahl and Morrison, 1974 Measurement of Compaction and Subsidence Suffolk Extensometer June 1982 – Dec. 1995 Depth = 484 m Chesapeake Bay West Point Franklin Extensometer Oct. 1979 – Dec. 1995 Depth = 255 m Major Pumping Centers Suffolk Miles Franklin 0 25
GW Availability Problems • Ground water has been drawn down significantly in parts of the Coastal Plain. • Places along the fall line are declining more rapidly than other areas. • Field data is showing water levels are lower than model predictions in these areas. • Salt water intrusion and land subsidence is occurring. • Management tools haven’t changed in 20 years.
Water Planning pre-2003 • “Every one for themselves” planning • “Water has always been there” planning • “Won’t be a drought worse than the 1930s drought” planning • Started to plan when water use reached 80% of permitted capacity (VDH) • Extended drought from 1999-2002 exposed some inadequacies in planning
Regional Water Supply Planning Programs (due 2011): Upper Shenandoah River Basin Southwest Region (Cumberland Plateau, 5 Northern Virginia RC (CSPDC) LENOWISCO, & Mount Rogers PDC’s) Rappahannock County & Washington Greene County & Stanardsville 1 New River Valley Region (NRVPDC) Madison County & Madison (Town) Albemarle County, Charlottesville Craig County & New Castle (RVARC) Culpeper County & Culpeper (Town) City, Town of Scottsville Greater Roanoke Region (RVARC) Northern Neck PDC West Piedmont PDC Spotsylvania County & Fredericksburg City 1 Upper James River Basin (CSPDC & The Towns of Blacksburg & Christiansburg are working together on a separate regional program. Due to scale, this region is not represented on the map. Louisa County & Towns RVARC) Fauquier County & Towns Region 2000 LGC Cumberland, Powhatan, Buckingham County & Dillwyn (CRC) Goochland, & Henrico Counties Local Water Supply Planning Programs & Deadlines: Prince Edward County & Farmville Hanover County & Ashland 2 Submitted 2008 Northern Shenandoah Valley PDC Caroline County & Bowling Green Charlotte County & Towns Middle Peninsula PDC Submitted 2009 Halifax County & Towns Northampton County & Towns (ANPDC) Submitted 2010 3 Lake Country Region (Southside PDC) Accomack County & Towns Lunenburg County & Towns (CRC) (ANPDC) Hampton Roads PDC The Towns of Port Royal, Chincoteague, Warrenton, 2, 3, 4, 5 & Hillsboro submitted local programs in 2010 Appomattox River Water Authority (Chesterfield, Prince George, & Dinwiddie Counties; Cities of Petersburg & Colonial Heights; Town of McKenney) & the City of Hopewell 4 Submitted 2011
Local Plan Elements • A description of existing water sources, water use, water resource conditions and water demand management actions • An assessment of projected water demand (30-50 yrs) • A statement of future need • An analysis that identifies potential alternatives to address projected deficits in supplies • A drought contingency and response plan
It’s hard to predict the future… • We’re probably going to need more water. • It’s likely that we’ll need more storage. • It’s also likely we will need to be more conjunctive. • And, more regional in meeting our needs.
Challenge of State-wide Water Resource Planning • State of Virginia is faced with challenges: • State-wide water supply planning requirement • “Grand-fathered” withdrawals, un-permitted reported withdrawals, permitted withdrawals • Complex interaction of intakes, storage and demand • Some resources at or near full allocation • Managing for multiple beneficial uses • Making sense of the plans -> Cumulative Impact Analysis • Assist water supply planners in data collection/organization • Connect to real time/agency sources of data • Do modeling of long term basin wide water availability
State Plan Vision: Business as Unusual • Use locally derived data for demands, use and alternative sources of future supply • Collaborative meta-modeling emphasizing “Systems Dynamics” approach to linking traditional gage models, empirical models, and watershed models • Evaluate existing and future basin-wide cumulative impacts to beneficial uses to identify opportunities for optimization and shared vision planning • Integrate planning and permitting through common modeling framework
SYR and Water Supply Plans • DEQ is generating Storage to Yield ratios for all streams in the Commonwealth • Water supply plans will provide projections of need, and alternatives to fulfill those needs • Compare projected needs to current and projected storage, and SYR for basins • Encourage basin-wide collaboration between localities with excess SYR with localities with deficient SYR • Locality A:- 3 MGD demand • 300 MG storage • High SYR • As a Region:- 12 MGD demand • 500 MG storage • Balanced SYR • Locality B:- 9 MGD demand • 200 MG storage • Low SYR
Future Challenges and Opportunities Who will pay for water resource data needs. Climate change is mostly about impacts to water. Population growth continues in areas without sufficient water resources. Current system promotes inequity. Will we overcome our need to 1) rationalize the risk of being wrong, 2) deny the need for change in our behavior?
Scott Kudlas, Director Office of Surface and Ground Water Supply Planning (804) 698-4456 scott.kudlas@deq.virginia.gov http://www.deq.virginia.gov/watersupplyplanning/homepage.html