Providence's Hurricane Barrier, Part 2: How It Really Works

Providence's Hurricane Barrier, Part 2: How It Really Works

The real guts of the hurricane barrier lie across the mouth of the Providence River. That structure contains three large moveable gates and a pumping station containing five 10-foot diameter, 4500 horsepower pumps.

The gates are 40 feet wide and allow small pleasure craft to pass through when open, but larger ships which used to dock at the lower end of the river no longer can pass and, instead, dock at the Port of Providence located south of the barrier. The gates take a half hour to lower into position and effectively prevent the waters of Narragansett Bay from flowing into the Providence River and potentially flooding the downtown area of the city.

The five large pumps are designed to pump water from the Providence River into Narragansett Bay, thus preventing the continuously flowing river water from backing up with no place to go except back into the city. Each pump can kick 630,000 gallons of water per minute into the Bay. With all five pumps in operation at once that’s over 3.1 million gallons per minute! Controls and instrumentation for the gates and the pumps are located inside the pumping station. The barrier is periodically inspected and the pumps are routinely cranked up and tested. They underwent a $3 million overhaul in 2006.

As an interesting sidelight, having the barrier is a bonus for WaterFire events. During low tide, closing the barrier keeps water levels up in the Providence, Moshassuck and Woonasquatucket rivers.

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