Gulf Branch is located in north Arlington.
Gulf Branch drains directly into the Potomac River.
Rapid Stream Assessment Technique Scale: Good
In 2011, we assessed all the streams in the County as part of the Stormwater Master Plan Update. The assessment used the Channel Evolution Model to evaluate which sections of the streams are actively eroding to prioritize them for stream restoration. During that assessment, Gulf Branch was evaluated to be a priority stream for stream restoration given that approximately 45 percent of the stream length assessed was found to be in an actively eroding state. In addition, only about 30 percent of the stream channel has been stabilized.
About Gulf Branch
In 2011, a watershed retrofit study of the Gulf Branch subwatershed was completed. In 2019, the design process for Gulf Branch restoration was begun, with ongoing opportunities for public input. Learn more about the Gulf Branch restoration and provide your feedback.
Macroinvertebrate Monitoring Data
The stream monitoring site is located just downstream of Military Road and the Gulf Branch Nature Center.
Macroinvertebrates commonly found are:
- Black flies
- Net-spinning caddisflies
- Small minnow mayflies
In fall 2011 and spring 2012, we contracted a professional monitoring group to collect family/genus-level macroinvertebrate and fish data at each of our volunteer monitoring sites.
Bacteria Monitoring Data
There is one bacteria monitoring site on Gulf Branch located just downstream of Military Road and Gulf Branch Nature Center. Learn more about bacteria monitoring data.
- Blue line: Measured bacteria levels.
- Orange line: Primary contact recreation water quality standard, 235 E. coli CFU/100 mL. Primary contact recreation activities have a high probability for total body immersion or ingestion of water, like swimming, canoeing and kayaking.
- Gray line: Secondary contact recreation water quality standard, 1,173 E. coli CFU/100 mL. Secondary contact recreation activities don’t have a high probability of total body immersion or water ingestion, like skipping rocks or fishing.
- The graph below can be enlarged by clicking on it.