More than 80 percent of the Upper Long Branch watershed is located outside of Arlington. One-third of the stream channel is within the County. Upper Long Branch flows through Glencarlyn Park.
Upper Long Branch drains directly into Four Mile Run. The drainage area is 4.7 square miles.
Rapid Stream Assessment Technique Scale: Good
Sites along Upper Long Branch scored 32 out of 56. Based on the amount of impervious cover and the results of a detailed stream inventory, Upper Long Branch ranks as one of the “most impacted” watersheds in the County according to the Watershed Management Plan.
Macroinvertebrate Monitoring Data
There has been a volunteer monitoring station on Upper Long Branch since 2002. The site is located adjacent to Glencarlyn Park, and is downstream from Carlin Springs Road and the Long Branch Nature Center.
Macroinvertebrates commonly found are:
- 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 Upper Long Branch, located downstream of Carlin Springs Road and the Long 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.