Little Seneca Creek


Little Seneca Creek is an stream in Montgomery County, Maryland, roughly northwest of Washington, D.C.

Geography

The creek drains portions of Clarksburg, Germantown, and Boyds. It rises south of Damascus and flows southward about to Little Seneca Lake, a reservoir created by construction of a dam on the creek. The reservoir empties to the lower portion of the creek, which flows south about to Seneca Creek, which drains to the Potomac River and the Chesapeake Bay.
A portion of the creek below the lake is a cold water stream that supports wild rainbow and brown trout populations.
The creek and reservoir are a drinking water source as part of the Little Seneca system, an emergency water supply for the metropolitan Washington, D.C. area.

Water quality issues

In 1994, the Montgomery County Council anticipated population growth in the Little Seneca watershed and imposed some restrictions on housing development and other new construction in part of the watershed, in order to preserve water quality before development accelerated. A "Special Protection Area" was designated that requires additional controls for stormwater runoff, beyond those required of all new projects.
However, the county reported in 2010 that its recent requirements for new construction projects had not been sufficient to prevent water quality impairment. Several large land development projects were constructed in Clarksburg and elsewhere in the watershed over the past several years. The county conducted biological monitoring of stream conditions and documented declines in water quality associated with the new construction. More comprehensive site designs to minimize stormwater runoff, such as conservation design or low impact development designs, were recommended.
In 2014, the County Council set additional limits on development projects in order to protect the quality of the Tenmile Creek tributary and adjacent habitat.

Tributaries