The CSO (Combined Sewage Overflow) Abatement Project

For most people, the three-mile underground tunnel is, in fact, both out of sight and out of mind — exactly where most of us like to keep raw sewage. But the CSO (Combined Sewage Overflow) Abatement Project could produce the most visible change in upper Narragansett Bay water quality in decades.

There is, indeed, light at the end of this tunnel, and the story of the project’s planning and construction signifies how the Bay Community can rise to even the most daunting challenges to preserve the Bay for future generations.

The Bay Bash

The Project by the Numbers

Q&A with
Ray Marshall


Providence, Pawtucket and Central Falls’ combined system of storm drains and sewer lines was ancient — more than 100 years old. In the past century, growth had far outgrown capacity. The result was that even moderate rain events caused stormwater to flood the system, pushing raw sewage into overflow pipes that drained directly into the Bay, closing beaches and contaminating shellfish.

Save The Bay’s involvement dates back more than 20 years. In 1988, we published a report entitled A Raw Deal: Combined Sewer Overflow Pollution in Rhode Island. The report warned that “…untreated waters from combined sewer overflows pose many threats to the health of the Bay, its marine inhabitants and human consumers. Untreated overflows contain raw sewage, industrial wastes and urban runoff. Within each of these categories are many hazardous substances that have innumerable impacts on the environment.”

The big dirty secret was now commonly known: The Bay had become a toilet.

The report acknowledged that the Narragansett Bay Commission (NBC), formed six years earlier in 1982, was taking steps to address combined sewer overflows, albeit via the most “cost-effective” measures rather than long-range solutions. The problem was huge. A system that would contain most rain events would be enormous. And because of the nature of underground construction, the effort would cost hundreds of millions of dollars.

In 1992, Save The Bay persisted with Topher Hamblett testifying at a public hearing against an NBC draft permit proposed by DEM. An article in the July-August Bay Bulletin was headlined “Narragansett Bay Commission Draft Permit Inadequate: Save The Bay Urges Stronger Requirements for Combined Sewage Overflow Discharges.” The finger was pointed at DEM.

NBC’s first comprehensive Combined Sewer Overflow Abatement Program, released in 1993, called for constructing seven underground storage facilities and three deep-rock tunnel segments at a then-staggering cost of $467 million. Not long after, the EPA announced new standards for CSO compliance that more or less restarted the analysis and planning process.

“It was a struggle,” recalls Save The Bay’s Narragansett Baykeeper John Torgan. “Relations were not the best for some time because we were strenuously opposing a proposed NBC sludge incinerator at Fields Point.”

In 1996, Save The Bay asked for a series of stakeholder meetings on CSOs and later participated, calling for a comprehensive plan requiring a significant investment — but one that had to be made to protect the upper Bay. Some 25 stakeholder groups were identified, including several who were adamant that rate-payers should not be saddled with the cost. 

Three years later, after long and sometimes bitter public debate, DEM signed off on the Phase I plan. Construction of the $342 million project began in 2002.

Here is today’s headline: Phase I is has been completed on time and on budget. The benefits to the Bay will become increasingly obvious. NBC estimates a reduction in overflow volume of about 40% after Phase I facilities are complete and approximately 98% after all phases are complete. The number of annual shellfishing bans will drop dramatically, and some areas off limits to shellfishing could reopen for the first time in decades.

“Save The Bay and the Narragansett Bay Commission are both deeply committed to protecting and enhancing water quality in Narragansett Bay,” said NBC Executive Director Ray Marshall. “And although we may not always have agreed on how that should be achieved, I think we’re all looking forward to a great future working together for clean water. The future of Narragansett Bay is especially promising with our organizations embracing an approach of mutual cooperation.”

Today, Save The Bay staff works with NBC on monitoring Bay conditions and sharing data on other water quality concerns.

“Our professional working relationship — our mutual respect — is better than at any time,” Torgan says. “While we are focused on common goals, I also believe it’s understood that Save The Bay remains an independent organization that will take tough stands when it comes to what’s best for the Bay.”

And as was the case in the CSO stakeholder process, plenty of people rely on Save The Bay’s leadership.

Upper Narragansett Bay is not a toilet. The Bay Community agrees on that point and, through an open process that included strong leadership and solid project management by the Narragansett Bay Commission, a significant improvement in Bay water quality has resulted.

It is well worth celebrating.

Photos and illustrations courtesy of Narragansett Bay Commission.