Bearing a price tag of more than $550 million and a timetable that spans over two decades, the Narragansett Bay Commission’s Combined Sewer Overflow Project has been labeled by some as the “big dig” of Rhode Island.
And with construction of the 16,000-foot long tunnel that will stretch from Fields Point to the Foundry set to begin this spring, officials at the Narragansett Bay Commission are reluctant to compare the project to Boston’s own “bigger dig,” except to say that it is a necessity.
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“In old cities like Providence when the sewers were built there was only one pipe put in to handle both sewage and rain,” said Jamie Samons, public affairs director for the Narragansett Bay Commission. “When we have large volumes of rain it overwhelms the system and there isn’t enough room in the pipe. The discharge is the combined sewer overflow and the legacy of a 100-year-old sewer system. Its presence violates the Clean Water Act.”
Under a Consent Order from Rhode Island Department of Environmental Management, the Narragansett Bay Commission is required to present a plan that would put it in compliance with federal standards. The result is the Combined Sewer Overflow Abatement Program.
“This is in response to a federal mandate,” Samons said. “It is something we have to do.”
The project, separated into three phases calls for the construction of a three mile tunnel, 26 feet in diameter, 250 feet underground. Starting at Field’s Point, the plans call for the tunnel to run under Allens Avenue to South Main Street and then take a westerly turn along the Woonsaquatucket River, ending at the Foundry site.
The first phase includes the construction of the tunnel and the underground pumping station at Fields Point.
“What we are looking to do is the get the most bang for the earliest buck,” Samons said. “In the first phase completed we will have captured more than 40 percent of our coverage area.”
The first phase of construction alone is expected to cost about $227 million dollars. According to Samons, some of the funding is coming through bond money left over from the creation of the Bay Commission, other money is coming through the clean water bond, and still other funding is coming in the form of zero interest loans. Still, it’s not enough.
“The remaining portion will have to come through user charges,” she said. “It’s something we hate to do, but have to.”
In fact, customers of the Narragansett Bay Commission are already feeling the project’s impact. A 25 percent rate increase was approved by the Public Utilities Commission earlier this year. In all, by the end of the 20-year project, Samons said, rates could be doubled.
“Obviously it’s something we are hoping not to do,” she said. “We are all working hard to see that it doesn’t happen, but it is possible.”
Joseph Pratt, a representative of the Louis Berger Group, the program manager for the project, said by the end of the three phases the system will eliminate the sewer overflow at an average of one billion gallons a year.
“Ninety seven percent of the overflow will be eliminated,” he said. “That’s more than the federal standards require. There is no way to eliminate all overflow, but we think this is the best solution.”
Untreated sewage
Created by the Rhode Island General Assembly in 1980, the Narragansett Bay Commission operates two wastewater facilities – Bucklin Point in East Providence, and Fields Point in Providence. The commission serves the cities of Providence, Central Falls, Pawtucket, Cranston and East Providence, as well as the towns of Johnston, North Providence, Cumberland, Lincoln, and Smithfield.
Each year, the Narragansett Bay Commission estimates that 2.2 billion gallons of untreated sewage is released into Narragansett Bay and its tributaries, including the Blackstone River, Moshassuck, Providence, Seekonk, Woonasquatucket and West Rivers.
The solution to the problem, Samons said, is a new abatement system
“Unfortunately it’s not a simple fix,” she said. “We have been looking at the problem for 10 years or so.”
The problem is also fueled by a consent agreement reached between the commission and DEM. According to the agreement, DEM has waived the non-compliance fines, which could have been as much as $25,000 per day, while the commission continues to meet a set of scheduled deadlines in the creation of a Combined Sewer Overflow Abatement Program.
As part of the process the commission initiated a stakeholders group early in 1994, with member representing business, environmental and governmental interests. In August of 1997, the stakeholders agreed to select Alternative 17, the current program being initiated by the commission, because it had the lowest maintenance cost. In addition, Samons said the stakeholders believed the plan would result in good water quality because most of the storm flows that are stored in the tunnel are also provided with a high level of treatment.
“We examined all the possible ways of doing this and we found that (the Narragansett Bay Commission) had sufficient capacity to treat this if we could hold until the storm subsided,” Pratt said.
The process of construction is one that has never before been done in Rhode Island. The plans call for the tunnel to be built underground without disturbing traffic above.
“If you think about it in construction terms, it’s like the chunnel from England to France,” Samons said. “There is a drill that bores through the layers or rock 250 feet below the surface.”
And while most local contractors may not have the underground experience needed for the bulk of the project, it doesn’t mean there won’t be a need for workers. John Kaplan, of Gilbane Building Co./Jacobs Associates, the construction manager, said work on the tunnel will be round the clock five days a week.
“This is an exciting and challenging project,” he said. “Every major contract except the pump station has underground work.”
The first phase alone has more than 20 contracts, many of which will result in additional subcontracts, Kaplan said.
The plan also calls for a two-year review period between each phase of the construction process. According to Samons, this time will be used to evaluate how the system is working and research new technologies that have arisen.
The final draft of the plan was approved by DEM in 1999. In July of the same year DEM issued a “Finding of No Significant Impact.”
“This plan reflects many years of hard, thoughtful work on the part of the professionals and stakeholders who undertook a careful examination of a very complex and challenging Combined Sewer Overflow abatement issue,” said Jan Reitsma, director of DEM. “There has been an extensive evaluation of environmental benefits and impacts as well as alternatives, which indicate that the proposed projects will be the most environmentally sound, as well as cost effective, means to control the charges. Given the long history of planning and evaluation and the quality of analysis to date, DEM strongly believes it is time to move forward and to implement improvements and clean up the urban areas around Providence.”
