PRINCE WILLIAM COUNTY, Va. — The Lake Jackson Dam in Prince William County is leaking and a consultant has been brought into determine the cause of the problem, Coles District Supervisor Marty Nohe announced Tuesday.
The consultant comes after employees with the Prince William County Public Works Department have been left scratching their heads as to why water is seeping from the 85-year-old concrete structure. Nohe said the leak is a concern because of the small community of homes cropped up around the dam site. The structure sits west of the Town of Occoquan on the river of the same name. After it was built, a body of water formed to what is now Lake Jackson.
Last year, residents in the Lake Jackson area noticed lower than normal lake levels. Subsequently, public works crews found “two “toe” drains on the down stream side of the Lake Jackson Dam that are releasing a significant amount of water,” according to a county report. There is a concern that if water has accumulated inside the core of the dam, safety may be an issue here, according to a county report.
More from Supervisor Marty Nohe’s website on what has been done to investigate the problem:
The County engaged the services of a nationally known dam consultant to investigate the cause(s) of the toe drain activation, as well as been in discussion with the State Dam Safety Engineer for the NOVA region. The investigative work included:
-Underwater diving investigation of both the upstream and downstream face of the dam
-Coring holes into the dam crest to investigate the dam interior with remote control cameras
-Dewatering the interior of the dam with pumps
-Use of dye tracer tests to determine seepage areas.
*Please note this work was exploratory in nature and did not include any repairs or remediation.
Nohe last month met with contractor Micheal Baker Corporation, which submitted a report outlining rehabilitation options for the dam. Those options are posted to the Coles District website.
After large rainstorms impacted the area last May, county officials became concerned about the safety of the dam and ordered the evacuation of nearby homes.
