A Limnological Analysis of Lake Manassas, with an Updated Baseline Through 2010

Lake Manassas is an approximate 706 acre man-made lake located in greater Prince William County near the town of Gainesville, Virginia. The lake was created in 1968 on Broad Run to serve as the primary water supply for the City of Manassas and its residents. The Lake Manassas watershed lies within the greater Occoquan River watershed which drains into the Potomac River and Chesapeake Bay. Water within Lake Manassas and its tributaries has been monitored since 1971 and this thesis presents a comprehensive limnological analysis of the Lake with an analysis of water quality impacts over time.

Lake Manassas remains an enriched or eutrophic system, meaning the levels of nutrients and biomass production in lake waters is above desired standards. Nutrient loading occurs via a stream network with the largest contributor being Broad Run which is consistent with previous water quality studies.

The lake serves as the sole water source for nearly 40,000 residents and businesses and ensuring clean and safe water is of significant importance. Close monitoring in conjunction with the implementation of appropriate management practices within the watershed are necessary to prevent water quality from becoming significantly degraded.