Managed by the Fairfax County Water Authority, it provides an important water supply to surrounding settlements in northern Virginia, with an output of 17 million US gallons a day (64,000 m3/d) to 1.2 million people, including over half of the population of Prince William County.

[2] Despite being a major fresh water source, Occoquan Reservoir is listed on Virginia's Dirty Water List, with recorded high levels of phosphorus, turbidity, low dissolved oxygen, the presence of copper sulfate and the growing presence of pharmaceuticals, largely due to human land uses, population pressure and poor management.

[2] As a result, in 1971, A Policy for Waste Treatment and Water Quality Management in the Occoquan Watershed was approved by the SWCB.

[3] The Occoquan Boat Club (OBC), founded in 1979 by Rick Evans, is a major boating club located on the reservoir, organizing rowing, sponsoring crew races, sending teams to regattas, and advocating rowing in Northern Virginia.

[4] The club operates singles, doubles, sweep fours and sculling quads rowing sessions on the lake.