Roanoke River watersheds in Virginia
Source: Environmental Protection Agency Surf Your Watershed
The dam for Lake Gaston required a Federal license, and the 50-year license was scheduled to expire in 2001. Re-issuance of the license was the responsibility of the Federal Energy Regulatory Commission (FERC). During the relicensing process, FERC authorized a rare interbasin transfer east of the Mississippi River, allowing Virginia Beach to tap into Lake Gaston to withdraw up to 60 million gallons per day for municipal water to supply a locality that was outside of the Roanoke River watershed.
Virginia Beach (in partnership with the City of Chesapeake, which has a 1/6th share of the project) is one of two major metropolitan areas on the coastal plain in Virginia that are outgrowing the water supplies within their local basin. Both cities are unable to extract more groundwater, in part because of a "bolide" that impacted 35 million years ago. That collision shattered the rock formations and trapped salt water underground, so deep (greater than 300') groundwater near Hampton Roads requires expensive desalinization.
Newport News tried to build the King William reservoir and import water from the Mattaponi River, north of the James River. Virginia Beach focused on an existing reservoir south of the James River. Virginia Beach has now completed its pipeline to Lake Gaston, and since 1997 has imported freshwater from the Roanoke River. Norfolk has sufficient water supplied by the Blackwater and Nottoway Rivers plus four deep wells located in Suffolk. Norfolk does treat water pumped from Lake Gaston, then pipes it on to Virginia Beach and Chesapeake.1
The Virginia Beach pipeline is the longest drinking straw in Virginia - 76 miles long and 60 inches wide. It stretches from Lake Gaston, west of I-95 on the North Carolina border, crosses the Meherrin, Nottoway, and Blackwater rivers, and exits the Roanoke River basin entirely before reaching Ennis Pond in Isle of Wight County and then Lake Prince, a reservoir in the City of Suffolk. Additional local pipes allow tourists in oceanfront hotels on Atlantic Avenue in Virginia Beach to turn on their taps and get fresh water from the Roanoke River.
Sucking water from the Roanoke River to supply southerh Hampton Roads, just before the river flows into North Carolina, was very controversial. North Carolina used its authority under the Coastal Zone Management Act (CZMA) to try to block FERC from authorizing the pumping station at Lake Gaston. Both FERC and the National Oceanic Atmospheric Administration in the Department of Commerce (the Federal agency that is the "umpire" to determine if projects are consistent with a state's coastal zone management plan) approved the proposal of Virginia Beach.
Virginia Beach claims that downstream of the Lake Gaston dam, flow in the Roanoke River through North Carolina could be reduced 1% (and up to 4% in a major drought) - but the withdrawals will not reduce the level of Lake Gaston itself, because the intake structure for the pipeline is at the downstream end of the reservoir (after water has already flowed through the lake).
However, levels in Kerr Reservoir (also known as Buggs Island Lake) upstream of Lake Gaston could be lowered 2-4 inches. Virginia Beach acquired water rights in Kerr Reservoir from the Corps of Engineers, to supplement the natural flow of the Roanoke River in times of drought. During a drought, the Corps of Engineers will release water from Lake Kerr into the upper end of Lake Gaston. The City of Virginia Beach withdraws the water at the lower end of Lake Gaston at Pea Hill Creek, thus maintaining the level of Lake Gaston while still extracting sufficient water for the urban customers. Since Kerr Reservoir is primarily a flood control project where water level fluctuations range up to 12 to 22 feet, the environmental and economic impact of an additional drop of 2-4 inches to meet Virginia Beach needs was not considered significant enough to block the project.
Virginia Beach considered alternatives to the interbasin transfer from the Roanoke River. These included desalinating brackish or salty seawater, drilling local groundwater wells, recycling wastewater from local swage plants, and building new impoundments on the Assamoosick Swamp or the Appomattox River. Pulling massive amounts of water from the aquifers underground was expected to result in seawater intrusion, damaging private wells in the region as the saltwater replaced the freshwater underground. As the city pumped extra water from underground, the current flow of rainwater to recharge the aquifers would be interrupted.
The city's answer to one key question is particularly significant: 2
