Watersheds
No matter where you are, you are in a watershed.
A watershed is an area where the water above-ground and below-ground drains to the same stream, river, lake, bay or ocean.
Watersheds can be very small, such as the watershed for the stream that may flow through your local park. These small streams join together to form larger and larger waterways with larger and larger drainage areas like the Chesapeake Bay and Mississippi River watersheds.

Watershed map .gif repurposed from the Rockingham County, NC

Our County's watersheds are determined by the geography, topography and waterflow.
Montgomery County has over 1,500 miles of streams. Pretty impressive!
There are two major watersheds within the County: the Potomac River watershed, which covers 88% of the County, and the Patuxent River watershed, which covers the other 12%.
How the land and streams are cared for upstream has a significant impact not only to our local environment but to the ecosystem downstream as well.
Find Your Watershed Map
Want to know which watershed you live in and how healthy it is?Use this Interactive watershed map.
County Watersheds
Montgomery County is made up of eight major watersheds and almost 150 smaller watersheds. The map at the top of the page shows streams, tributaries, lakes, and other water features within Montgomery County as well as their health and condition.Anacostia
Subwatersheds:
- Little Paint Branch
- Northwest Branch
- Paint Branch
- Sligo Creek
Cabin John Creek
Lower Monocacy
Subwatersheds:
- Bennett Creek
- Fahrney Branch
- Little Bennett Creek
- Furnace Branch
Lower Potomac Direct
Subwatersheds:
- Little Falls
- Muddy Branch
- Rock Run
- Watts Branch
Patuxent River
Subwatersheds:
- Hawlings River
- Lower Patuxent
- Upper Patuxent
Rock Creek
Subwatersheds:
- Lower Rock Creek
- Upper Rock Creek
Seneca Creek
Subwatersheds:
- Dry Seneca
- Great Seneca
- Little Seneca
Upper Potomac Direct
Subwatersheds:
- Broad Run and Horsepen Branch
- Little Monocacy and Monocacy River
How Do Watersheds Affect Us?
Healthy watersheds offer many valuable functions and are essential for appreciating the local natural environment.
By protecting our watersheds and preventing pollution, we help secure our quality of life and reduce the costs of government cleanup programs. Also, keeping our local waters clean helps protect the water supply and habitat for people and animals that live downstream, allowing them to experience the same benefits.
In a healthy watershed, there are:
-
Recreational opportunities such as fishing, canoeing or boating
-
Habitats for wildlife and fish. Good water quality is important for both fish and their food sources.
-
Lower costs for drinking water. The dirtier the water, the more expensive the treatment before being piped to your home.
-
Aesthetically pleasing surroundings. Clean waterways offer beauty in the landscape.
-
Escape from urban development. Waterfronts are peaceful places that people can enjoy.
-
Homes, businesses, and roads protected from flooding and other natural disasters.
-
Less polluted waters creating better public health and safety. Polluted water can be a human health hazard.
-
Reduced tax burdens to clean up and protect the environment.