It won’t be today or tomorrow, but the City of Woonsocket, Rhode Island, is planning to permanently shutter its Sewage Sludge Incinerator (SSI) that has been in operation since the 1970s. That was clear from the language in the August 25th City Council Resolution and the quotes from City leaders following the unanimous approval to start negotiations with the Narragansett Bay Commission (NBC) to take over ownership of the City of Woonsocket’s wastewater facility and SSI. The reference to closing the SSI came up five times in the two-page Resolution, as in the clause about making wholesale changes to the treatment facility and entering into negotiations with a third party with the “strict condition that the Incineration Facility must be permanently shuttered and closed by a date certain.”

The Woonsocket SSI facility represents 105 dry tons per day of sludge processing capacity and, according to the Massachusetts Department of Environmental Protection report by Tighe & Bond, by far the largest in the region. Also according to that same report, the SSI still has an estimated 28 years of useful life.

The Woonsocket SSI is co-located on the property with the City’s water resource recovery facility (WRRF) on Cumberland Hill Road in Woonsocket, on the banks of the Blackstone River. The original multiple hearth incinerator constructed in the 1970s was upgraded in 2007 to fluidized bed technology to comply with new federal air pollution limits. The City contracts for both WRRF and SSI operations with Jacobs Engineering and Synagro, respectively. All three entities are the subject of ongoing legal action by the Rhode Island Attorney General’s office taken in March 2023 (see 2023.03.15-Complaint-State-v-City-of-Woonsocket-et-al-1.pdf (rhodeislandcurrent.com)) after a spate of discharge permit violations.

According to news reports, the City says that is has decided to part ways with Jacobs and Synagro and is looking to negotiate a transfer of ownership to the NBC. The Resolution acknowledges that the City is still under long-term contracts with Jacobs and Synagro but that it is in the best interests of the residents that the City move on from the ownership and operation of the WRRF and SSI. Those contracts are for services through the year 2032. However, there is a clause in the contract requiring the City to take over maintenance of the SSI from Synagro by July 1, 2027. The City is looking at major capital improvements at the SSI and WRRF, estimated at $40 to 50 Million in the Resolution. Synagro is required to provide daily operating service through 2032.

Woonsocket had previously announced its intention to cut liquid sludge acceptance by 50% as of January 1st, 2026, with the rest being eliminated as of 2027. The Warwick Sewer Authority and others have had to scramble to find new outlets for their liquid sludge. It’s not only Rhode Island facilities that are dependent on the Woonsocket SSI to take care of their sludges, but as the MassDEP report shows, a lot of the liquid sludge is coming from just across the border in Massachusetts. Although Woonsocket has not issued any plans or guidance on these changes, the SSI operator Synagro has been notifying customers and changing contracts. The City of Cranston SSI, operated by Veolia, has been inundated with calls, making room for more in-state sludge at its multiple hearth incinerator which still accepts liquid sludges.

NEBRAMail reached out to NBC, a NEBRA member, for comment. NBC made it clear that they are just starting formal negotiations and plan to perform their due diligence by evaluating the condition of the treatment facility, the assets NBC would be assuming, and potential liabilities from taking over ownership and operation of Woonsocket’s infrastructure. That process could take a while. NBC currently owns/operates systems in Providence and East Providence and they are no stranger to taking over failing sewer systems – or shutting down an SSIs. 

The Rhode Island Department of Environmental Management expressed concerns to the media. Joseph Haberek, head of RIDEM’s surface water protection and water quality programs was quoted as saying:

“We all rely on the Woonsocket incinerator as a disposal option,” Haberek said. “That would be problematic if they were to stop accepting biosolids.”