Occoquan Reservoir is a reservoir in northeast

Virginia Virginia, officially the Commonwealth of Virginia, is a state in the Mid-Atlantic and Southeastern regions of the United States, between the Atlantic Coast and the Appalachian Mountains. The geography and climate of the Commonwealth ar ...

, southwest of

Washington, D.C. ) , image_skyline = , image_caption = Clockwise from top left: the Washington Monument and Lincoln Memorial on the National Mall, United States Capitol, Logan Circle, Jefferson Memorial, White House, Adams Morgan, ...

, straddling part of the boundary between

Fairfax County Fairfax County, officially the County of Fairfax, is a county in the Commonwealth of Virginia. It is part of Northern Virginia and borders both the city of Alexandria and Arlington County and forms part of the suburban ring of Washington, D.C. ...

and

Prince William County Prince William County is located on the Potomac River in the U.S. state of Virginia. As of the 2020 census, the population sits at 482,204, making it Virginia's second-most populous county. Its county seat is the independent city of Manassas ...

, west of

Alexandria Alexandria ( or ; ar, ٱلْإِسْكَنْدَرِيَّةُ ; grc-gre, Αλεξάνδρεια, Alexándria) is the second largest city in Egypt, and the largest city on the Mediterranean coast. Founded in by Alexander the Great, Alexandria ...

. It is formed by the Occoquan Dam on the

Occoquan River The Occoquan River is a tributary of the Potomac River in Northern Virginia, where it serves as part of the boundary between Fairfax and Prince William counties. The river is a scenic area, and several local high schools and colleges use the r ...

. Managed by the

Fairfax County Water Authority Fairfax County Water Authority (FCWA or more recently Fairfax Water for short) is the main water company in the Northern Virginia region of the United States, and one of the four major water providers in the Washington, D.C. metropolitan area (the ...

, 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. The Occoquan Reservoir is officially under

, despite being on the border with Fairfax County. The major drainages tributary to the Occoquan Reservoir can be divided into two principal sub-basins: Bull Run and Occoquan Creek. Despite being a major fresh water source, Occoquan Reservoir is listed on Virginia's Dirty Water List, with recorded high levels of

phosphorus Phosphorus is a chemical element with the symbol P and atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Ear ...

, turbidity, low dissolved oxygen, the presence of

copper sulfate Copper sulfate may refer to: * Copper(II) sulfate, CuSO4, a common compound used as a fungicide and herbicide * Copper(I) sulfate Copper(I) sulfate, also known as cuprous sulfate, is an inorganic compound with the chemical formula Cu2 SO4. It ...

and the growing presence of pharmaceuticals, largely due to human land uses,

population pressure Population pressure, a term summarizing the stress brought about by an excessive population density and its consequences, is used both in conjunction with human overpopulation and with other animal populations that suffer from too many individuals ...

and poor management. In 1968, the Virginia State Water Control Board (SWCB) commissioned a study of the Occoquan Reservoir and its tributary streams to draw up a plan of sustainable management for the reservoir. A 1970 analysis stated that the reservoir was "highly

eutrophic Eutrophication is the process by which an entire body of water, or parts of it, becomes progressively enriched with minerals and nutrients, particularly nitrogen and phosphorus. It has also been defined as "nutrient-induced increase in phytoplank ...

...", and further, that "the sewage plant effluents are mainly responsible for the advanced stage of eutrophication occurring...". As a result, in 1971, A Policy for Waste Treatment and Water Quality Management in the Occoquan Watershed was approved by the SWCB.

Recreation

The reservoir can be accessed by

Interstate 95 Interstate 95 (I-95) is the main north–south Interstate Highway on the East Coast of the United States, running from U.S. Route 1, US Route 1 (US 1) in Miami, Miami, Florida, to the Houlton–Woodstock Border Crossing between M ...

, which has attracted fishing recreational activities on the lake since 1961.

Largemouth bass The largemouth bass (''Micropterus salmoides'') is a carnivorous freshwater gamefish in the Centrarchidae ( sunfish) family, a species of black bass native to the eastern and central United States, southeastern Canada and northern Mexico, but ...

bluegill The bluegill (''Lepomis macrochirus''), sometimes referred to as "bream", "brim", "sunny", or "copper nose" as is common in Texas, is a species of North American freshwater fish, native to and commonly found in streams, rivers, lakes, ponds and ...

, black and white

crappie Crappies () are two species of North American freshwater fish of the genus ''Pomoxis'' in the family Centrarchidae (sunfishes). Both species of crappies are popular game fish among recreational anglers. Etymology The genus name ''Pomoxis'' ...

channel catfish The channel catfish (''Ictalurus punctatus'') is North America's most numerous catfish species. It is the official fish of Kansas, Missouri, Iowa, Nebraska, and Tennessee, and is informally referred to as a "channel cat". In the United States, the ...

flathead catfish The flathead catfish (''Pylodictis olivaris''), also called by several common names including mudcat or shovelhead cat, is a large species of North American freshwater catfish in the family Ictaluridae. It is the only species of the genus ''P ...

northern pike The northern pike (''Esox lucius'') is a species of carnivorous fish of the genus '' Esox'' (the pikes). They are typical of brackish and fresh waters of the Northern Hemisphere (''i.e.'' holarctic in distribution). They are known simply as a ...

, and

white perch The white perch (''Morone americana'') is not a true perch but is a fish of the temperate bass family, Moronidae, notable as a food and game fish in eastern North America. In some places it is referred to as "Silver Bass". The name "White perc ...

are fished on the lake despite some pollution problems. 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. The OBC has 180 members and has over 19 shells, recognizable by their red and black striping on the bow. The club operates singles, doubles, sweep fours and sculling quads rowing sessions on the lake.

References

{{authority control Reservoirs in Virginia Protected areas of Fairfax County, Virginia Protected areas of Prince William County, Virginia Lakes of Fairfax County, Virginia Bodies of water of Prince William County, Virginia