Boston’s Charles River has long been iconic for its place in the city’s history, but had more recently become an icon of source water contamination. Since the mid-20th century, the river’s water quality has received harsh criticism and as recently as 1995, the U.S. EPA gave the body a “D-” grade in its annual water quality assessment, determined by the E. coli levels in samples collected monthly at 10 river locations.
Since then, thanks to a concerted effort by the city, the grades have steadily risen. 2016 marked the third year in a row that the river has received a “B+” from the EPA.
“The improvement in water quality in the Charles River illustrates the point that it is possible to change the status quo, even in the face of the challenges of an urban environment,” said Elisabeth Cianciola, an aquatic scientist with the Charles River Watershed Association (CRWA).
The EPA credits the turnaround to three major initiatives: the reduction of combined sewer overflow (CSO), the stringent enforcement of water quality standards, and a crackdown on illicit discharges. A fourth effort, reducing runoff, has been implemented to improve an emerging algae problem and achieve higher grades in the future.
A 1997 negotiated agreement between the EPA, the State of Massachusetts, and the Massachusetts Water Resources Association (MWRA) required the MWRA to reduce CSO. This agreement was modified in 2005 to require even further reductions, becoming the “MWRA Long-Term CSO Control Plan.” The plan minimizes overflows into the river during storms by redirecting flow through alternate pipes. Sewer separation projects allowed for stormwater and wastewater to travel in different pipes throughout much of MWRA’s service area.
“Prior to the ’90s, there were 19 CSO outfalls, dumping 1.7 billion gallons per year of sewage into the lower Charles River,” an EPA representative told Water Online. “Since 1988, sewage discharges have been reduced … to currently 17.5 million gallons of sewage discharging per year, a 99 percent reduction.”
The EPA and the State are responsible for enforcing National Pollutant Discharge Elimination System (NPDES) permits and that has become a significant factor in the river’s improvement. The same agreement that required the MWRA to cut down on CSO also gave them greater ability to hold parties that violate quality standards accountable.
“Reporting mechanisms linked to the EPA’s court settlement with MWRA and permits issued through the NPDES program serve as a means for enforcement agencies such as the EPA and [the Massachusetts Department of Environmental Protection] to require municipalities and others who are permitted to discharge wastewater into the Charles River to take action,” Cianciola said. “Enforcement actions were more common in the early years of the illicit discharge detection and elimination programs (IDDE) and have petered out as illicit discharges have been successfully eliminated.”
Eliminating Illicit Discharges
The IDDE programs have targeted illicit discharges — usually caused by cracked and leaking sewer pipes or faulty connections to the storm drain system — by systematically identifying faulty connections between laundry machines, roof gutters, and residential wastewater pipes to municipal storm drains, largely eliminating sewage contamination of the stormwater that flows into the river.
“Since 2004, these efforts have eliminated 54,000 gallons of sewage-contaminated stormwater flowing into the Charles River per day, approximately 20 million gallons per year,” said the EPA representative.
In 2007, research was showing an excess of nutrients, primarily phosphorus, in the river, according to the EPA. Today it still struggles with runoff from fertilizers and roadways bringing in the nutrients which create toxic algae blooms.
To protect urban rivers like the Charles from the nutrient problem, the EPA issued an updated Municipal Separate Storm Sewer System (MS4) permit in Massachusetts this year.
“Over time it will ensure that stormwater is clean enough to protect quality in the Charles,” the agency representative said. “The permit requires communities to step up their efforts to find and remove illegal sewer connections to the stormwater system, to keep raw sewage out of the Charles and other local waters. In addition, the new permit requires that the Charles River communities make significant reductions in the discharge of phosphorus, which stimulates algae blooms in the Charles.”
The Road Ahead
Significant work lies ahead if the Charles will ever achieve an “A+” grade.
Cianciola said that CSO needs to be even further reduced to fully achieve CRWA’s water quality goals. This would require new, major stormwater management projects, but no effort to implement them is currently underway.
“This could be done by reducing the amount of impervious area, such as rooftops, parking lots, and roads, in the watershed and by redirecting stormwater runoff to the ground instead of to storm drains,” Cianciola said.
Despite the long road ahead, the dramatic improvement in the Charles River provides a positive lesson for other communities struggling with their own urban water quality. Regardless of the direction they’re currently headed.
Image credit: "Charles River Esplanade Aerial" Massachusetts Water Resources Authority (MWRA) © 2010 used under an Attribution 2.0 Generic license: https://creativecommons.org/licenses/by-sa/2.0/