Blog - Charles River Watershed Association

5 Methods Used by CRWA to Monitor the Charles River

Posted by Julie Dyer Wood

9/18/14 10:08 AM

The Charles, like any natural environment, is a complex, interconnected, living, changing system. At CRWA, our work is guided by the philosophy that we cannot address and manage problems in the Charles without understanding them. Collecting and analyzing our own data is a critical piece of this process and the backbone of CRWA’s advocacy and design work. Whether monitoring is conducted by staff, interns or volunteers, everyone follows strict monitoring protocols to ensure we collect the most accurate data available. In celebration of World Water Monitoring Day, read on to learn more about five ways CRWA monitors the Charles every day. 

READ: CRWA's Volunteer Monitoring Program 2016 Final Report

  1. Basic Physical Parameters – Every month, CRWA volunteers collect temperature and depth readings at 35 sites along the Charles, and these relatively simple parameters can tell us a lot about the river. Temperature (pictured top right) is very important for biological processes and can indicate pollution sources or unusual conditions. Depth helps us track the relative river flow across the seasons and over the years. CRWA has been monitoring these parameters since 1995, building the most comprehensive dataset available on the Charles River

  2. Sample Collection and Analysis – CRWA volunteers and staff regularly collect water samples, which are then taken to external laboratories for analysis. CRWA collects samples for bacteria all along the river on a monthly basis throughout the year and on a weekly basis in the Lower Basin (downstream from Watertown Dam) during the summer and fall, as part of our summertime Water Quality Notification Program. E.coli bacteria concentrations indicate whether sewage is likely present in the river. Four times a year, volunteers also collect samples which are analyzed for nutrients (nitrogen and phosphorus), total suspended solids, and chlorophyll a. 

  3. Biological Monitoring – A new addition to CRWA’s field science program in 2013, benthic macroinvertebrate monitoring helps characterize the general ecosystem health of a stream section. This sampling methodology is limited to wadeable sections of streams and rivers and involves the collection and identification of small bugs and other organisms living in the stream sediment and vegetation. By inventorying these critters, which have varying abilities to tolerate pollution (highly sensitive to very tolerant); we can learn a great deal about the water quality. Unlike fish, these organisms cannot move out of degraded areas, therefore a river stretch with only highly pollutant tolerant organisms likely has very poor water quality. 

  4. Hotspot / Investigative / Response Monitoring – CRWA also regularly monitors the river in response to possible pollution sources. This may involve follow up sampling after a high result from one of our regular monitoring sites, pipe or outflow monitoring, or just responding to the scene of a reported issue and conducting a visual survey or “sniff” test.  

  5. Cyanobacteria Monitoring – A relatively recent issue in the Charles, cyanobactera (a.k.a. blue-green algae) can pose a threat to humans and other mammals when they are present in large concentrations or “blooms”. Cyanobacteria produce cyanotoxins which can cause minor to serious reactions in humans and can be fatal to dogs that drink the water. Summertime blooms have become relatively common in the Charles River Lower Basin. CRWA uses an optical probe (pictured bottom right) to look for pigments unique to cyanobacteria and also collects samples which are viewed under a microscope so species can be identified and counted. CRWA also works with the Massachusetts Department of Conservation and Recreation (DCR) and surrounding communities to notify the public in the event of a bloom.  

Want to get involved in protecting the health of the Charles River? Become a CRWA Citizen Scientist and help us monitor water quality! To start, please fill out CRWA's below volunteer application form today:

Help Protect the Charles by Becoming a CRWA Citizen Scientist Today!


Topics: Charles River Cleanup, Fish and Wildlife, Charles River, Stormwater, Stormwater Management, Thermal Pollution, Pollution, Legislation and Policy

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About Charles River Watershed Association:

One of the country's oldest watershed organizations, Charles River Watershed Association (CRWA) was formed in 1965 in response to public concern about the declining condition of the Charles. Since its earliest days of advocacy, CRWA has figured prominently in major clean-up and watershed protection efforts, working with government officials and citizen groups from 35 Massachusetts watershed towns from Hopkinton to Boston. Initiatives over the last fifty years have dramatically improved the quality of water in the watershed and fundamentally changed approaches to water resource management.