Location
The Nichol Run and Pond Branch watersheds (7.7 square miles and 8.4 square miles, respectively) are located in the northernmost part of Fairfax County and drain to the Potomac River, the source of drinking water for many residents.

Major Streams and Tributaries
Nichol Run: Major tributaries include Jefferson Branch and Harkney Branch as well as some unnamed streams. Several small streams that drain directly to the Potomac have been included in the Nichol Run Watershed for planning purposes.

Pond Branch: This watershed is made up of three smaller watersheds. Pond Branch itself is in the northernmost portion of the watershed. Clarks Branch is to the south and east, and Mine Run is to the south of that and meets the Potomac River at the upstream end of Great Falls.

Unique Features
River Bend Park and most of Great Falls Park are in the Pond Branch watershed.