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CRWA Water Quality Projects and Data

Water Quality in the Charles River: an overview

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 Notification Flagging Program
CRWA's Water Quality Notification 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 eleven 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.

Public Health Fish Consumption Advisory

Massachusetts keeps an online database of fish consumption advisories. Find it here.

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.

2012 Charles River Report Card

Listen to Bill Walsh-Rogalski, EPA Region 1, Announce the 2012 Grade

The EPA’s 2011 Charles River report card, announced at the Charles River Cleanup on Sunday, April 22nd, gave the Charles River a B grade, down slightly from the past several years when the Charles got a B+.  EPA’s grade is based on data from CRWA’s volunteer water quality monitoring program, one of the most extensive water quality monitoring programs in the nation.  The lower grade was due to heavy rain storms in 2011, which flush pollution off streets, parking lots, and even lawns into the river.  The same heavy rains in 2011 caused an unusually high number of combined sewer overflows (also called CSOs, which happen when a mix of polluted runoff and sewage is released into the river when sewer pipes are overwhelmed).  Since climate change predictions tell us we should expect more heavy rain events – as well as more droughts like the one we are currently in – CRWA has been working hard over the past decade to install and test systems and technologies to reduce pollution and sewer overflows caused by storm runoff.  See our Blue Cities® page for examples.

The gains we have made in cleaning up the Charles are dramatic – our first grade from EPA was a ‘D’ – and winning the International Riverprize cements the Charles River’s stature among the world’s great rivers.  But CRWA and our partners still have a tremendous amount of work to do to protect those gains, and get us up to the ‘A’ grade we all know is possible.  Slipping from a B+ to a B is a reminder that we still have a lot to do.

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Updated April 23 2012