WATER QUALITY

CRWA Water Quality Projects and Data

Blue-Green Algae in the Charles
Blue-green algae (formally known as cyanobacteria) has been present in the Charles River for years, but the issue has recently become a concern due to the type and quantity of blue-green algae that is present. Get more information about this issue, learn what CRWA is doing to help, and view fact sheets and a field guide to learn to identify the blue-green algae.

Daily Water Quality Flagging Program
CRWA's Flagging Program monitors the river's daily health from July to October. Our color-coded flags signify whether or not the river is safe for boating at nine locations from Watertown to Boston. Data available: daily or weekly summertime bacteria results for Lower Basin.

Monthly Water Quality Monitoring
CRWA's monthly volunteer program collects data used to identify problems in the river and trends in water quality, and to track the progress of efforts to clean up the Charles. Data available: monthly tables since 1995, for e. coli, fecal coliform, and various other parameters.

"Find it and Fix it" Program
This three-year program identifies, monitors and helps to eliminate non-point source pollution threatening the health of the Charles and Mystic Rivers. The program involves volunteers conducting visual shoreline surveys, water quality monitoring, and education for the public and municipal officials about stormwater issues. Data available: Results for wet and dry weather monitoring at seven tributaries.

Water Quality in the Charles River: an overview

Water quality in the Charles River has significantly improved since 1995 when the U.S. Environmental Protection Agency (EPA) Region 1 launched an ambitious effort - based on CRWA's science - to restore the Charles to fishable and swimmable conditions by 2005. Improvements in wastewater treatment and collection, and the elimination of many point source (end-of-pipe) discharges have resulted in considerable water quality gains. Much of the river meets water quality standards for fishing and swimming in dry weather conditions. However, as Earth Day 2005 has passed and the goal of a fishable, swimmable Charles River year-round has not been fully achieved, there is still much work to do. CRWA's programs play a key role in monitoring and improving water quality to support the achievement of the current goal of a fishable and swimmable river by 2010.

Most of the Charles River, its tributaries, and watershed lakes and ponds remain "impaired" by various pollutants, meaning they do not meet water quality standards for their prescribed designated uses in all weather and all seasons. Many of these impairments are attributable to stormwater pollution and remain the main impediment to realizing a fishable, swimmable Charles. The Charles River watershed is the most urbanized in Massachusetts, with 20% of the state's population, and highly impervious land cover, so it is not surprising that urban and suburban stormwater runoff remain serious problems for the river.

Because CRWA's advocacy work requires strong scientific underpinnings based on a holistic understanding of the way the watershed works, CRWA began a comprehensive water quality monitoring program for the Charles River and its tributaries in 1995. This includes a foundation of water quality data generated by volunteers, which provides baseline information of the river's health and allows for the analysis of spatial, temporal, and meteorological water quality trends for a number of water quality parameters. Through this program, CRWA has established the most consistent and comprehensive data set for the Charles River watershed, and one of the most extensive water quality data sets of any river in the nation.

In addition to monthly monitoring by volunteers, CRWA staff conduct targeted water quality monitoring and collect critical data to verify and/or gather additional information about polluted areas of the river. Data collected by CRWA volunteers and staff are used widely by regulators, municipalities and students in tracking pollution and is used by the EPA to determine the Annual Charles River Report Card.