Water Supply Planning in Hampton Roads: Options for an Uncertain Future The State of Virginias Water Resources October 28, 2015 Whitney S. Katchmark, P.E. Hampton Roads Planning District Commission HAMPTON ROADS 2 Regional Water Supply Plan 3 Completed in 2011 17 localities First time a document consolidated information on sources, demands and water contracts in the region Supplies met projected demands for 30 years. Two specific issues were identified as sources of uncertainty in this analysis #1 Regulatory Climate (availability of groundwater permits) #2 Natural Constraints (climate change) Retrieved from DEQ Groundwater Permitting website:4 WHO ARE LARGEST GROUNDWATER USERS? 5 PROPOSED PERMIT CUTS Most public water systems also have surface water supply. Chart only shows groundwater. 6 Groundwater 22% Reservoirs & river intakes 78% Groundwater 22% Reservoirs & river intakes 78% Total Supply = 196 mgd Total Supply = 75 mgd 7 Public Water Supply 8 Southside Public Water Systems Western Tidewater Public Water Systems 9 SUPPLY WITHOUT GROUNDWATER PERMITS CURRENT SUPPLY DEMAND Impact of Potential Permit Cuts on Public Water Supply 10 SUPPLY WITHOUT GROUNDWATER PERMITS CURRENT SUPPLY DEMAND SUPPLY WITH REDUCED GROUNDWATER PERMITS Peninsula Public Water Systems 11 SUPPLY WITHOUT GROUNDWATER PERMITS CURRENT SUPPLY DEMAND 12 Impact of Potential Permit Cuts on Public Water Supply SUPPLY WITHOUT GROUNDWATER PERMITS CURRENT SUPPLY DEMAND SUPPLY WITH REDUCED GROUNDWATER PERMITS Future Domestic Demands (irrigation wells not included) 13 14 Peninsula Reuse Opportunities 15 Southside Reuse Opportunities 16 Western Tidewater Reuse Opportunities ISSUES Alternatives are expensive. No remedy for costs sunk into groundwater infrastructure that would no longer be used if we switch sources. Population growth and economic development opportunities are difficult to accurately project. Regulations do not identify a process for reducing allocations or prioritizing needs. 17 Inject clean water into the aquifer to: Provide a sustainable supply of groundwater throughout Eastern Virginia Reduce the rate of land subsidence Protect the groundwater from saltwater contamination Sustainable Water Recycling: Aquifer Replenishment System 18 Graphic is animated Sustainable water recycling 19 Groundwater Modeling Results Potomac Aquifer water levels before and after injection Injection Sites Depletion Recovery Depletion Recovery Water Levels in 50 years if all permitted users pump their maximum permitted amount. Water Levels in 50 years with HRSD Aquifer Replenishment System (injection wells). INTEGRATED PLANNING? Concept addresses multiple environmental objectives / challenges Likely that funding and equity will be harder to address than technical issues Only collaborate if you have to (because its hard and time- consuming) From Dutch Dialogues 20 21 POTENTIAL SOLUTIONS 22 Optimize Groundwater or Surface Water in Region Optimize Groundwater or Surface Water in Region Develop New Sources Wastewater Reuse WHY IS DEQ PROPOSING CUTS? Declining water levels Land subsidence and loss of storage Reversal of groundwater flow leads to salt water intrusion Supporting Data & Authority Model simulations, measurements, and regulations 23 Groundwater System Our aquifer system has a shallow end & deep end. 24