CRWA's Water Quality Notification Program presents the daily flag colors of the river's health, which signify whether or not the river is safe for boating at ten boating locations from Watertown to Boston. Flag colors are based on E. coli and cyanobacteria levels. The following forecasts are based on real-time environmental conditions as part of a collaboration between CRWA and CESN at UMass Boston.
CRWA estimates E. coli levels using a model that takes into account a variety of environmental factors including antecedent rainfall and river flow. CRWA collects river samples for bacteria weekly to verify the model forecast. Cyanobacteria monitoring is conducted at least every two weeks. The weather and water data in this model is sourced from the CESN weather station at Community Boating and the USGS Waltham river flow gauge. Read more about the development of CRWA's bacteria prediction model.
Indicate inconclusive data to preclude a possible health risks
Indicate potential health risks