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Watts Branch Subwatershed

The Watts Branch subwatershed is in the Potomac River Basin drainage of Montgomery County and consists primarily of residential land uses. Like the subwatersheds of many middle Potomac tributaries, this watershed is influenced by historical development patterns that saw the evolution of major roads, like Interstate 270.

The City of Rockville occupies the headwaters of Watts Branch, and over time the Interstate 270 corridor has grown and now traverses the upper section of the subwatershed. Pockets of high-density commercial and residential development, important components of the County's overall economy, are located in the headwaters of many of the Watts Branch tributaries.

Land uses gradually transitions to lower densities and predominately residential uses in the downstream reaches of Watts Branch.

Image of Watt Branch Waters

A Journey Through Watts Branch

Resource conditions are good in the upper and western tributaries of Piney Branch and the Lower Sandy Branch. Conditions are fair throughout the rest of Watts Branch. This fair condition reflects the observed flow problems stemming from uncontrolled runoff in much of the subwatershed. Although rated as fair, Lower Watts Branch supports a fish community of approximately 25 species. Many of the more tolerant species are well represented, although some sensitive fish species are found in fewer numbers. Smallmouth bass are found in many of the pools in Watts Branch, and colorful greenside darters can be observed in the rocky bottom runs.

The Piney Branch tributary was designated a Special Protection Area (SPA) in 1995 in recognition of the high-quality stream condition in this tributary and the need for special measures to protect this resource. The high water quality and cool, steady baseflow in this tributary are important to maintaining conditions downstream. This fragile tributary has a relatively small channel and is particularly sensitive to flow conditions. Careful management and implementation of special protection area requirements should enable this stream to recover from what should be temporary impacts to regain the high-quality conditions that led to SPA designation.


What Can I Do to Help the Watts Branch Subwatershed?

Individuals interested in helping to protect the health of the Watts Branch can contact the Watts Branch Alliance. This non-profit organization of local citizens works together to support the natural environment surrounding the Watts Branch subwatershed for all to enjoy.