Blog - Charles River Watershed Association

The Muddy River Then and Now: Water Quality in 2006 vs. 2016

Posted by Elisabeth Cianciola

1/23/17 5:33 PM

The Muddy River, which runs a course of 2.9 miles from Jamaica Pond to the Charles River, is the most significant tributary of the lower Charles River. As a prominent feature of the famous Emerald Necklace parks, its fate was marginally better than most tributaries of the lower Charles in that it was only partially buried and not completely buried in the frenzy to make more land available around Boston in the early 1900’s. Nonetheless, the river was seriously impacted by this human interference. The river lost some of its natural ability to flush sediment that accumulates in the river as a result of stormwater runoff and was unable to adequately dissipate flooding across its floodplain. Severe flooding in the 1990’s made it clear that the human-altered Muddy River system was not working, and an effort to restore the river’s natural characteristics was needed.

Jaya and Richie sample at the Muddy River

CRWA interns Richie and Jaya sample water from the Muddy River.

Twenty years after the catastrophic flood that shut down Kenmore Station and caused serious damage to much of the other infrastructure in the Fenway, Phase I of the Muddy River Flood Damage Reduction and Environmental Restoration Project was completed in 2016. This phase of the project “daylighted” a section of the river between Park Drive, the Riverway, and Brookline Avenue that had been buried in the 1940’s to create more space for roads and parking. In addition to providing flood control, one of the five objectives of the project is to improve water quality in the Muddy River. The Muddy River was listed on the Massachusetts Department of Environmental Protection’s 2014 Integrated List of Waters as being poorly suited for aquatic organisms due to excessive amounts of sediment, phosphorus, and E. coli bacteria. To help evaluate the effectiveness of the project in meeting this objective, Northeastern University conducted water quality monitoring on the Muddy River between 2006 and 2009 under the oversight of the Muddy River Restoration Project Management and Maintenance Oversight Committee (MMOC). In 2016, CRWA replicated much of the work that was performed by Northeastern University to determine whether or not Phase I of the restoration had impacted water quality in the Muddy River.


CRWA’s monitoring results showed that water quality in the Muddy River did improve downstream of the Phase I project area under dry weather conditions. While phosphorus concentrations increased by approximately 18% upstream of the project area, they actually decreased by approximately 16% downstream of the project area.The stretch of the Muddy River between Willow Pond and the Longwood Avenue bridge saw large increases in phosphorus pollution and increases in sediment pollution in excess of 100%, underscoring the need for not only the dredging proposed in Phase II of the project, but also the need to improve erosion controls and stormwater management in this part of the Muddy River watershed. Aquatic organisms such as river herring rely on visual and olfactory cues to locate their spawning grounds after spending the summer out at sea, and water pollution can interfere with these cues.


Seagrant Map

The Muddy River carries sediment into the Charles River, creating a shallow area (shown in light blue)  at the Muddy River Delta. Explore the interactive CRAB and MIT Sea Grant Chart of the Lower Charles River. 

Although E. coli bacteria levels observed during dry weather have improved since 2006, E. coli contamination still exceeds state water quality standards for swimming in dry weather and now exceeds both swimming and boating standards in wet weather. To help reduce E. coli bacteria concentrations in the Muddy River, watershed management in this area should include frequent inspection of wastewater infrastructure, stormwater infiltration using green infrastructure such as rain gardens and porous pavement, and landscape management that deters Canada geese.

To follow the progress of Phase II of the restoration project, visit the MMOC’s website

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Topics: Fish and Wildlife, Charles River, Pollution, Water Quality, Stormwater Runoff

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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.