Bacteria Results

Pathogens can be found in our rivers, and these pathogens pose a human health risk. West/Rhode Riverkeeper monitors indicator bacteria levels to inform our community of that risk. These indicator bacteria serve as a surrogate for the pathogens which may cause illness in humans. They come from a variety of sources, including failing septic systems, sewer overflows or leaks, pet waste, and livestock. During significant rainfalls, the possibility always exists for elevated and unsafe bacteria levels.

Note: The Anne Arundel County Health Department advises that after a rainfall, all Anne Arundel County beaches are under a no swimming/no direct water contact advisory for 48 hours due to predicted elevated bacteria levels from rainwater runoff and increased health risks.

“Is it safe to swim in the water?” Click here to see our answer.

Concerned about “Vibrio”? Maryland Dept of the Environment has a one-page guide HERE.

West/Rhode Riverkeeper conducts weekly bacteria monitoring between Memorial Day and Labor Day. This Monitoring is supported by the Chesapeake Bay Trust, Baltimore Gas and Electric as well as individual site sponsorship by the West River Sailing Club. If you would like to receive the results in a weekly email, please let us know by emailing Jeff Holland at

Bacteria Results: (Greater than 104 cfu/100 ml are considered elevated bacteria levels. These samples are highlighted in red)

You can also download the Swim Guide mobile phone app to access our weekly bacteria data!