A group of concerned citizens founded an association in 1965 to save a polluted river, building six decades of Charles River restoration and climate resilience work.
The Charles River earned its unflattering nickname “Dirty Water” honestly. Decades of industrial pollution, raw sewage, trash, and even discarded cars fouled the 80-mile river flowing from Hopkinton through 23 Massachusetts communities to Boston Harbor. When a group of concerned citizens founded the Charles River Watershed Association in 1965, they took on one of the country’s most degraded urban waterways, using science, advocacy, and legal action as their primary tools.
Charles River restoration and climate resilience work began with unglamorous groundwork. In 1974, CRWA partnered with the Newton Conservation Commission to convince authorities not to rebuild the breached Bemis Dam, opening fish and wildlife passage that had been blocked for decades. That same year, the organization helped establish the Natural Valley Storage Area, protecting 8,000 acres of wetlands that prevent downstream flooding, replenish water supplies, and filter pollutants before they reach the river.
The 1990s brought CRWA’s most consequential sewage victory. Advocacy for the Massachusetts Water Resources Authority’s Long-Term Combined Sewer Overflow Plan led to an innovative engineering solution reducing sewage releases into the river by more than 95%, while saving ratepayers hundreds of millions of dollars. In 1994, CRWA also launched its Volunteer Monthly Monitoring Program, which has since grown to more than 80 volunteers collecting water samples monthly at 35 locations, building the most extensive water quality dataset the Charles River has ever had.
Charles River restoration and climate resilience efforts extended into dam removal throughout the 2000s and 2010s. CRWA partnered with state agencies to breach the Bleachery Dam in 2005, improving fish passage, and worked with the Town of Bellingham in 2016 to fully remove the aging, hazardous Old Mill Dam, reconnecting the Charles with three tributaries including Mine Brook. That same decade, CRWA introduced the American Shad Restoration Program, bringing this native fish species back to waters it had been unable to reach for generations.
International recognition followed. In 2011, CRWA received the prestigious Thiess International Riverprize for visionary and sustainable excellence in river management. The organization’s Earth Day Charles River Cleanup earned national recognition from American Rivers for four consecutive years, honored for both the most pounds of trash collected and the most volunteers mobilized nationwide.
As climate change intensified flooding, stormwater pollution, and environmental injustice across the watershed, Charles River restoration and climate resilience work evolved to meet new threats. CRWA established the Charles River Climate Compact in 2019, a coalition of watershed cities and towns sharing information and designing joint projects to mitigate flooding and build resilience together, recognizing that climate impacts do not respect municipal boundaries.
Charles River restoration and climate resilience now emphasizes nature-based solutions and environmental justice, including dam removals that reconnect fish passage, rain gardens that protect climate-vulnerable neighborhoods, and a watershed-scale flood model developed with 20 partner cities and towns. Photo courtesy of CRWA.
The organization’s watershed-scale Charles River Flood Model, developed with 20 cities and towns, simulates how increased precipitation will affect communities while testing mitigation strategies before implementation. The tool earned the New England Stormwater Collaborative’s “Stormy Award” in 2023 for inspiring regional collaboration. That same year, CRWA’s interactive StoryMap “A River Interrupted,” explaining why removing defunct dams matters for river restoration, won the ArcGIS StoryMap of the Year award.
Charles River restoration and climate resilience increasingly center environmental justice alongside ecological outcomes. In 2023, CRWA partnered with the Town of Milford to unveil rain gardens and an infiltration chamber in a climate-vulnerable, environmental justice neighborhood, protecting residents from flooding, extreme heat, and drought while creating a permanent space for community environmental education.
Persistent advocacy against stormwater pollution produced results at the federal level. Following years of pressure from CRWA and the Conservation Law Foundation, including the threat of litigation, the EPA announced a new stormwater permit program in 2022 targeting previously unregulated commercial and industrial properties. By 2024, the EPA released an even more ambitious draft permit requiring rain gardens and infiltration systems on large private properties with significant impervious surfaces, directly reducing pollution entering the Charles, Mystic, and Neponset Rivers.
Current work continues across multiple fronts. Dam removal is now underway in South Natick, four years after local officials voted to remove the spillway and restore natural river flow. In Newton, CRWA collaborates with the city on Cheesecake Brook restoration, combining wet meadow maintenance with public education about the project’s significance for the broader watershed. In July 2026, the Healey-Driscoll Administration awarded CRWA and the Neponset River Watershed Association a grant to establish the Metro Boston Partnership, advancing ecological restoration and climate resilience across both watersheds’ combined 428 square miles.
Charles River restoration and climate resilience today explicitly honors the land’s original stewards. CRWA acknowledges its work takes place across the traditional territory of the Massachusett, Nipmuc, and Wampanoag Nations, committing to respectful engagement with Indigenous communities and recognizing them as past, present, and future caretakers of the watershed.
Nearly 60 years after concerned citizens first organized to save their polluted river, the Charles has become one of the cleanest, most celebrated urban rivers in the country. Yet CRWA’s own guiding philosophy insists clean is not an endpoint but an ongoing verb. As stormwater pollution, intensifying storms, and environmental inequities continue testing the watershed, Charles River restoration and climate resilience work carries forward the same combination of citizen science, legal advocacy, and nature-based solutions that transformed Dirty Water into a model for urban river recovery nationwide.
