Site work for a water / sewer project in Springfield, Virginia. Completed plans call for site work for a water / sewer project.

Fairfax County Board of Supervisors constructed Lake Mercer in 1985 for flood control purposes. Lake Mercer has an earthen dam embankment, vegetated overland emergency spillway, and reinforced concrete riser control structure, principal spillway pipe, and impact basin. Thirty-two residential structures as well as 5 road crossings are inside the inundation zone, resulting in the classification of the facility as a high hazard dam. The dam is located on South Run approximately 1,500 feet (ft) northwest of the Hooes Road and Triple Ridge Road intersection and maintenance access is connected to a gravel parking lot on Hooes Road. The dam creates a permanent pool (lake) which is approximately 20.0 ft deep with a surface area of 43.2 acres at elevation 216.3 ft National Geodetic Vertical Datum of 1929 (NGVD29). The dam is 60 ft high and 1,050 ft long with the top elevation at 252.0 ft (NGVD29). The structure consists of an earthen dam, a 25-ft-tall principal spillway to control normal flows, and a vegetated emergency spillway (200 ft wide in the right abutment) to protect the dam flows exceeding the 100-year flood. The principal spillway consists of a reservoir inlet structure, a concrete riser, and a 42-inch (in) diameter conduit and impact basin. The riser also has a 30-in-diameter crank operated circular sluice gate at the base of the riser for dewatering. The stem of the 30-in-diameter sluice gate has been damaged and is to be replaced with a new stem, stem guide and stop nut. Questions regarding the project may be directed to the DPWES, Maintenance and Stormwater Management Division (MSMD), Project Manager - Paul Reynolds at 703-877-2857. All work is to take place at Hooes Road, Springfield, VA 22153