State sues Woonsocket over repeated contamination of Blackstone River by sewer plant

Alex Kuffner, The Providence Journal
·4 min read

PROVIDENCE – The state has filed suit against Woonsocket and the operators of the city’s wastewater treatment plant, alleging violations of the Rhode Island Clean Water Act and other environmental laws in repeated discharges of partially treated sewage into the Blackstone River. 

The civil complaint filed in Superior Court, Providence, by Attorney General Peter F. Neronha and the Department of Environmental Management was announced at a news conference Wednesday. Flanked by DEM director Terry Gray and environmental advocates, Neronha described the lawsuit as necessary to protect the river, which empties into Narragansett Bay.

“The parties have had their chances,” he said. “The DEM has warned them and attempted to work with them for more than a year.”

The suit was filed after the latest release of sewage earlier this month. The DEM warned the public to avoid contact with the river after the discharge was reported on March 1. Although recent tests showed some improvements in water quality, the agency kept the advisory in place until after Tuesday’s rainfall. Gray announced it would be lifted Wednesday afternoon.

More on the sewage discharge:Sewage discharged from treatment plant into Blackstone River — again. Why it happened.

A stretch of the Blackstone River in Woonsocket.
A stretch of the Blackstone River in Woonsocket.

Woonsocket wastewater plant has been plagued with problems

It wasn’t the first time the plant has experienced problems over the last 18 months. After Woonsocket alerted the DEM to untreated discharges last June, the problem continued for more than a week and the agency warned people not to wade, swim, boat or fish in the river, or to consume fish caught in its waters.

Previous to that, the agency issued notices of noncompliance in November 2021 for staffing and equipment problems at the plant, and again in March 2022 after a sewage discharge was discovered during routine testing.

“There’s been upset conditions multiple times,” Gray said. “We’ve worked with them to try to correct the issue, but it’s come back more times than we’d like to see.”

Why were the sewer discharges happening?

The facility treats between 6 million and 9 million gallons of wastewater daily, making it the fourth-largest plant in the state. It’s owned by the city, which contracts operations to the Texas-based engineering firm Jacobs. The plant works in conjunction with a neighboring incinerator operated by Maryland-based Synagro that processes sludge and solid waste brought in from other treatment plants throughout southern New England. Synagro dewaters the liquid sludge to produce what’s known as “cake,” which is then incinerated.

The dewatering occurs in centrifuges, with the resulting low-solids liquid, or centrate, going to the wastewater treatment plant for further processing. Normally, it would go to the plant’s gravity thickener – which is shared by Synagro and Jacobs – for additional solids removal, but the aging thickener broke down last month. That means that more solids than usual are entering the plant, overwhelming its filtration systems and causing sewage that is only partially treated to enter the river.

More on the Blackstone River:A river runs through it – and 50 years later, an army of RI volunteers will clean it again

Before the cleanup known as Project ZAP began in 1972, the banks of the Blackstone River were often used as a dumping ground. This 1970 photograph, shot in northern Rhode Island, shows the scope of the problem.
Before the cleanup known as Project ZAP began in 1972, the banks of the Blackstone River were often used as a dumping ground. This 1970 photograph, shot in northern Rhode Island, shows the scope of the problem.

What has the city done to address the problem?

Synagro has installed “frac tanks” to settle out solids before the centrate goes to the plant, and the city has brought in a belt press to do the same. At the urging of the DEM, the city is also set to bring in a portable gravity thickener to replace the permanent thickener while it’s repaired over the next year.

Meanwhile, Synagro is accepting most sludge deliveries again after Woonsocket ordered a temporary suspension when the discharge began.

Steve D’Agostino, director of the city’s Department of Public Works, said the facility can function smoothly in treating waste from Woonsocket and neighboring communities. The problem is the amount of sludge trucked in from elsewhere, he argued. Informed on Wednesday of the lawsuit, he expressed disappointment.

“We’ve never been negligent,” he said. “We're always trying to run the best operation possible.”

But Jonathan Stone, director of Save The Bay, said that too much was done to clean up a river that was once among America’s most polluted to let the current problems go unaddressed.

“It’s an incredible success story,” he said of improvements in the river. “But to have a setback like this is an insult to the people of Rhode Island.”

This article originally appeared on The Providence Journal: Woonsocket sewage spills into Blackstone River triggers lawsuit