Tales of Stream Monitoring Fun
Lake Accotink Park
Friends of Lake Accotink Park
Friends of Accotink Creek

Friends of Accotink Creek and Friends of Lake Accotink Park hold biological stream monitoring workdays four times per year.
Thanks to all the volunteers who have joined us for this important data-collecting activity!

A lament for aquatic invertebrates penned by a Girl Scout who joined us for stream monitoring.
Her work challenges us all to care about Accotink Creek and our fellow creatures who must live in it.

December 16, 2017 Stream Monitoring:

A chilly but clear day with temperatures barely above freezing created challenging monitoring conditions for our small crew of three volunteers.

Our catch was dominated by species tolerant of poor conditions, such as aquatic worms, midges, and netspinner caddisflies, as is always the case on Accotink Creek. We did find a few creatures not often seen, namely two scuds and two non-netspinner caddisflies. We were also pleased to see a single hellgrammite in the net, an impressive bug once much more common in our creek. Our final stream health index was a sad score of 3 on a scale of 0 to 12. See the tabulated results here.

Excessive runoff from the ever-spreading asphalt is the main cause of fine sediment from accelerated streambank erosion which smothers streambed life. The next big insults to Accotink Creek from the I-66 and Braddock Road widenings will only make things worse. Tell your elected officials "Enough!". Take advantage of financial incentives to become part of the solution with Conservation Assistance..

September 9, 2017 Stream Monitoring:

A fine sunny day and mild temperatures in the 60's made for optimal monitoring conditions for our crew of eleven volunteers.

Our catches included several invertebrates we seldom see in Accotink Creek - 2 mayflies, 3 hellgrammites, 4 beetle larvae, and 1 gilled snail. Despite the welcome presence of these species indicative of better habitat conditions, their numbers were too small to raise the health score of Accotink Creek. With our catch dominated by species tolerant of poor conditions, such as aquatic worms, midges, and netspinner caddisflies, our final stream health index was a miserable score of 2 on a scale of 0 to 12. See the tabulated results here.

Excessive runoff from paved surfaces is the principal cause of Accotink Creek's poor health. Streambank erosion occurs when this runoff gushes from stormdrain outfalls and overwhelms streams. The erosion produces fine sediment which smothers streambed life. Take advantage of financial incentives to become part of the solution with Conservation Assistance..

Mussel Rescue, July 30 & 31, 2017:

Heavy thunderstorms sent the USGS stream gauge on Accotink Creek at Braddock Road above 2000 cubic feet per second in the early hours of July 29th. This flow rate is enough to push freshwater mussels out of the creek and leave them stranded on the banks and gravel bars. As the high water receded over the next few days, we searched the creek banks for stranded mussels.

Friends of Lake Accotink Park were first on the scene, with a human/canine team that rescued 10 mussels on July 30th.

On July 31st, the water had receded further. We found a record 56 stranded mussels and returned them to the creek. Some of the mussels may have been in the summer sun a little too long, but most appeared to have a good chance of recovery. There was sad evidence of many mussels that were not found in time, their freshly empty shells gaping open on the banks.

We also had help from a group of curious young summer campers enjoying a wading excursion to the creek. After a brief familiarization, their sharp young eyes spotted several mussels in peril. We may hope our young helpers will find and rescue a few more mussels as the creek level drops further.

See the rest of the mussel rescue photos here.

Read about our 2015 freshwater mussel biological survey.

Learn more about freshwater mussels.

Our June 10, 2017, Stream Monitoring:

We enjoyed bright, sunny, and warm weather, ideal for a late spring day in the outdoors.

We had a good turnout of 18 volunteers, including a number of Frost Middle School students completing a stewardship class assignment.

We were also joined by Audubon Naturalist Society for a demonstration of their Creek Critters smartphone stream monitoring app.

Arriving at the creek, volunteers divided into two groups, one for standard monitoring, and one for Creek Critters.

We had good bug hunting in terms of quantity, collecting 558 invertebrates in our first net, well in excess of the minimum 200 required. Quality was another story, as nearly everything we collected was just three species tolerant of impaired waters, netspinner caddisflies, aquatic worms, and midges. As usual, Accotink Creek achieved a stream health score of 4 on a scale of 1 - 12, well below the minimum acceptable level of 8. See the tabulated results here.

Streambank erosion, caused by excessive runoff from paved surfaces, smothers streambed life in fine sediment. Learn how you and your civic association can receive financial incentives to become part of the solution with Conservation Assistance.

Our March 11, 2017, stream monitoring:

Sunny but brisk temperatures just above freezing made for a good day of stream monitoring - better for the bugs than they had to endure during our last outing in December - and decidedly better than the tundra-like snowy cold front that blew in a few days later.

The bulk of our vounteers today were the energetic Girl Scouts of Troop 3048. Several of the scouts borrowed our too-large loaner boots and braved the water to serve as our collecting crew, stirring up the creek bed to send dislodged invertebrates drifting with the current into our waiting nets.

Our collection was mediocre today, dominated as usual by species tolerant of impaired waters, such as aquatic worms, netspinners, and midges. The quantity was also unimpressive, as we needed two nets to reach the minimum required number of 200 invertebrates. We did have three unusual finds today, a beetle larva, two aquatic sowbugs, and two scuds.

Based on the quantity and species range collected, Accotink Creek received its usual numeric score in the impaired range, achieving only a 4 on a scale of 12. This is well below the minimum of 8 needed to reach the healthy range. See the tabulated results here.

How can we change this score and see a healthy Accotink Creek again? Sediment is the major condition depressing stream health - caused when runoff from paved surfaces races down storm drains straight into streams, instead of soaking into the aquifer. The stream banks are scoured, depositing excessive fine sediment on the bottom, where it smothers the bottom-dwelling invertebrates that support the food chain. Stream erosion needs to be slowed at its upstream sources - learn about financial incentives through Conservation Assistance. to make the changes at your home or civic association property.