Dominion says it will adjust the flow of water in the North Anna River as part of a study on downstream impacts of a possible third nuclear reactor at North Anna Power Station.

The energy company will release water at two different flow rates over the Lake Anna dam Thursday through Monday. The study includes the impact of potentially raising Lake Anna's levels on wetlands, docks and piers.

The 13,000-acre lake in Spotsylvania, Louisa and Orange counties provides water to cool the two existing reactors at the power station.

Dominion received an early site permit for a third reactor last November and then filed a combined license to build and operate a new reactor.

The company says it has not yet made a final decision whether to build the reactor.