ARK/FOSC Volunteer Water Quality Monitoring Data

The 2021 Program

The Anacostia Riverkeeper (ARK)/FOSC 2021 Community Science water quality monitoring program wrapped up in Sept 2021. In its second year, the program expanded to 3 sites on Sligo Creek and 1 on its Long Branch tributary. ARK’s program includes a site on Northwest Branch and many other Anacostia watershed sites outside the Sligo watershed, plus the Rock Creek and Potomac river watersheds. Keep an eye out next April 2022 for information on how to participate next summer.

The FOSC Water Quality Monitoring team is active year round. Please contact Pat Ratkowski at [email protected] to learn more about FOSC’s WQ testing program and how to join the team.

Biweekly results for the ARK/FOSC program are prepared by Robbie O’Donnell, Watershed Programs Manager at ARK, and are posted below and on the ARK website.

June 16 2021 WQ table for Upper Anacostia Watershed
WQ testing results for Sligo watershed July 14, 2021

Tables, charts, maps and graphs courtesy of Anacostia Riverkeeper.

The 2020 program

September 2020 saw the successful conclusion of the summer’s new citizen science water quality monitoring program. Friends of Sligo Creek partnered with Anacostia Riverkeeper, Alliance for the Chesapeake Bay, Corazon Latino, and Friends of Lower Beaverdam Creek on a new volunteer-centric water quality monitoring program funded by the National Fish and Wildlife Foundation. COVID-19 shortened this year’s monitoring season, which ran from late June through late September.

Every other Wednesday morning, volunteers measured water temperature, air temperature, pH, and dissolved oxygen at two sites along Sligo Creek: in Silver Spring near the parking pull-off along Sligo Creek Parkway just downstream of Wayne Avenue, and at the confluence of Brashears Run and Sligo Creek in Takoma Park. They also collected and delivered water samples to Anacostia Riverkeeper for further bacterial and turbidity analysis at its lab. Volunteers at the Sligo Creek sites included Elinor Colbourn, Alan Abrams, Gwen Sletten, Eliza Reed, Jacob Konick and Ally Ratkowski-Howe.

2020 Findings

In brief, the 2020 data indicate that while Sligo Creek is well-oxygenated and usually quite clear (there is very little suspended sediment in the water), its coliform bacteria levels typically do not meet levels deemed safe for contact, and it carries a larger dissolved ion load than most of the other waterways in the study.

Two locations in Sligo Creek were selected for monitoring, labeled SC-1 and SC-2 on the map:


(1) SC-1 is between Wayne Ave. and Piney Branch Rd., near the parking pull-off along Sligo Creek Parkway; and


(2) SC-2 is near the first parking lot on Sligo Creek Parkway downstream from Maple Ave.

Photos showing both locations were posted on the websites of Anacostia River Keeper and Friends of Sligo Creek. The sites themselves were marked by orange tape tied to nearby trees.

Fleetwood Terrace water quality testing site

Fleetwood Terrace testing site