Lake Barcroft is a census-designated place (CDP) in Fairfax County, Virginia, United States.

The lake is named for Dr. John W. Barcroft, who owned and operated a mill on Holmes Run during the mid-19th century.

In 1942, the company installed 24 gates at the top of the dam to raise the spillway elevation five feet, increasing the reservoir size to 800 million gallons.

A year later, Colonel Joseph Barger and Associates purchased the reservoir, dam, and 680 adjacent acres of land for $1 million from the Alexandria Water Company.

The hurricane caused so much rain that the lake level rose above the top of the dam by 3 feet (0.91 m).

The LBWID is a quasi-governmental entity headed by three state-appointed trustees who are residents of Lake Barcroft.

The Lake Barcroft Association (LBA) came into being in 1992 when LABARCA and BARLAMA joined up into one private entity.

Largemouth bass, catfish, sunfish and a rare (non-stinging) fresh water jellyfish all inhabit Lake Barcroft.

[6] It is bordered to the northeast by Seven Corners, to the east by Bailey's Crossroads, to the south by Lincolnia, to the southwest by Annandale, and to the northwest by West Falls Church.

All common property is open to people living within the boundaries of the association and their authorized guests.

The Lake Barcroft Association employs seasonal lifeguards to protect its beaches during the summer months.

The residents organize occasional aquatic festivals, most notably Independence Day fireworks every July 4.

Fireworks are fired from one of the beaches, and residents crowd the water in their electric-powered or paddled boats to watch.