Environment
5:30 am
Wed March 19, 2014

Narragansett Bay Commission To Temporarily Close Sewer Overflow Tunnel

Starting today, the Narragansett Bay Commission will temporarily close a tunnel that’s part of a long-term, massive project designed to meet the federal clean water act. During heavy rains, that tunnel normally stores overflows of sewer and street runoff that are later treated and released into Narragansett Bay. Now the tunnel will be offline for the next three to four weeks.

When the Narragansett Bay Commission temporarily closes its sewer overflow tunnel, the Department of Environmental Management will revert to its old rules for shellfish closures for the Upper Narragansett Bay in order to protect people's health.
When the Narragansett Bay Commission temporarily closes its sewer overflow tunnel, the Department of Environmental Management will revert to its old rules for shellfish closures for the Upper Narragansett Bay in order to protect people's health.
Credit Ambar Espinoza / RIPR

Jamie Samons, public affairs officer for the Narragansett Bay Commission, said closing the tunnel is necessary in order to connect the first phase of the project to the second phase. That involves connecting the tunnel underneath Providence to a pipeline along the Woonasquatucket River.

“So in order to protect the workers and protect the infrastructure, we have to make sure that there is no flow when we make that connection,” said Samons. “When the phase one tunnel goes offline, for a temporary amount of time, we won’t have that added bit of protection against storm-related overflows that we’ve had for the past five years.”

To protect people’s health, the Department of Environmental Management will revert to its old rules for shellfishing closures for the Upper Narragansett Bay.  That means that the area known as Conimicut Triangle, part of an area known as Area A, will close for seven days after a half an inch of rainfall, and Area B will close for seven days after an inch of rainfall.

The tunnel will operate at a reduced capacity of about 60 percent through September. During this period, the DEM will use current criteria for shellfishing closures, as long as overflows don't exceed the tunnel’s temporary reduced capacity.

If overflows do exceed the tunnel’s temporary reduced capacity, then the DEM will close Conimicut Triangle, and conditional areas A and B for seven days beginning on the day of the overflow. The DEM will monitor these areas to determine whether they are safe to re-open earlier for shellfishing.