CRWA's Water Quality Notification Program uses a system of color-coded flags to indicate whether or not the river is safe for boating at ten boating locations between Watertown and Boston. Flag colors are based on E. coli and cyanobacteria (blue-green algae) levels.
CRWA estimates E. coli bacteria levels using models that take into account a variety of environmental factors including rainfall and river flow. CRWA collects water samples weekly to verify the model forecasts. Cyanobacteria monitoring is conducted every 1-2 weeks. Read more about the development of CRWA's bacteria prediction model.
Want to learn more about cyanobacteria, its history on the Charles, and what CRWA does to reduce its impacts and protect communities around the river? Read more here.
Thank you to Benjamen Wetherill of ACASAK Technologies for assistance developing and maintaining this automated system.
Updated 10:30 am on Thursday, August 22, 2019
Indicate potential health risks