Warm Springs Run flows from north to south and enters the Potomac River across from Hancock, Maryland. It drops about 400 feet in elevation over its 11.8 mile length. The narrow, 7,000 acre watershed is bordered on the east by steep hills cut by small intermittent streams in folded sedimentary rock. On the west, the steep sandstone ridge of Warm Springs Ridge releases numerous springs from deep groundwater emerging along its base. The largest spring system maintains a constant temperature of 73°F.

The watershed’s shale, sandstone, and siltstone have weathered into shallow soils that were depleted of organic matter by past logging and agriculture. Second and third growth forests of oak, hickory, Virginia pine, and patches of old meadow with native warm season grasses and invasive plants are scattered through the upper half of the watershed, which now contains extensive commercial and low-density residential development. Large sandstone quarries dominate the northwest quarter of the watershed. The community of Berkeley Springs (approximate population 3,000), with the small county seat of Bath (population 800), lies adjacent to Warm Springs Run in the upper half of the watershed and is prone to flash flooding. Finding and implementing ways to reduce this problem is one of WSWA’s central objectives.