PROVIDENCE, RI (AP) As construction crews prepare to burrow a 3-mi. tunnel beneath downtown Providence, officials offer assurances that the project designed to stem pollution in Narragansett Bay won’t become the next version of Boston’s Big Dig.
The Combined Sewer Overflow Abatement Program is expected to improve the water quality of Narragansett Bay by storing untreated sewage in deep rock tunnels until it can be pumped to a treatment facility. Currently, periods of heavy rainfall cause sewer lines in Providence and surrounding communities to overflow, sending millions of gallons of untreated sewage into the bay.
The result means closed shellfishing beds and beaches.
The project is estimated to take 22 years to complete, and could cost roughly $700 million, including inflation, said Jamie Samons, Narragansett Bay Commission spokeswoman.
But commission Chairman Vincent Mesolella said the plan won’t turn into a scaled-down Big Dig, Boston’s underground highway project that has been plagued with delays and rising costs. The Big Dig — originally estimated to cost $2.6 billion —now has a price tag of more than $14 billion.
“I will, with every ounce of my being, watch and maintain this budget so there’s no cost anticipated that shouldn’t be anticipated,” he said.
Samons said the project is being watched closely to ensure it remains within budget. In addition to an internal review by the Narragansett Bay Commission, Samons said, the Division of Public Utilities and the Public Utilities Commission are keeping tabs on the project’s cost.
In November, the state Supreme Court upheld a Public Utilities Commission ruling that an independent auditor must be hired to monitor the mammoth underground system.
“What the commission is looking for is someone who can help oversee the project and make sure it’s running effectively, efficiently, and hopefully within budget,” said Terry Mercer, spokesman of the Division of Public Utilities and Carriers. “It’s the biggest public works project in the state’s history and people want to make sure it goes smoothly.”
Mercer said the commission hopes to hire an independent auditor, called a “special master,” by the beginning of next year.
The majority of the funding is coming from Narragansett Bay Commission ratepayers at this point, Samons said. The federal government has kicked in approximately $6.5 million, and the state has devoted $26 million to the project.
“Over the 22 years that the Narragansett Bay Commission has been in existence, 98 percent of construction projects have come in on time, and on or under budget,” Samons said. “We are very confident.”
State officials gathered at a construction site June 16 to view the machine that will bore the tunnel along the Providence River. The tunnel, which will be more than three miles long and 26 ft. in diameter, will sit about 250 ft. below the city’s surface.
The tunnel project is just the first phase of the larger plan to bring Rhode Island into compliance with the federal Clean Water Act.
The tunnel will hold more than 60 million gal. of combined sewage and will reduce the annual volume of combined sewer overflow discharges by approximately 40 percent.
It is expected to reduce shellfishing closures by 47 percent in the northern half of the bay, and by 77 percent in the southernhalf, according to the Narragansett Bay Commission.
Gov. Don Carcieri, a former shellfisherman, said the project will open up the bay to more shellfishing, and preserve and nourish economic development and recreation along Narragansett Bay.
“We will have eliminated one of the major, major sources of pollution in Narragansett Bay,” he said.