Long Island Sound could be in trouble during storm

As Connecticut braces for the possibility of Hurricane Sandy’s landfall here early next week, environmental officials worry that the state’s already overtaxed sewage treatment systems could find themselves in deep trouble.

During last year’s October snowstorms and Tropical Storm Irene, hundreds of millions of gallons of partially-treated or raw sewage ended up in Long Island Sound. If Hurricane Sandy hits Connecticut at its projected strength, that situation is likely to repeat itself.

The news comes at a particularly bad time for Stamford’s Water Pollution Control Agency, which received a sharp rebuke from state officials earlier this month for failing to complete badly needed repairs on time. During last year’s October Nor’easter, the sewage plant sent 43 million gallons of partially treated sewage into Long Island Sound after a mechanical failure.

The plant’s supervisor, Bill Degnan, recently said the WPCA faces a “perfect storm” of infrastructure issues and needs at least $1 million for immediate repairs and upgrades. One large rainstorm could result in another waste dump into Stamford Harbor and ultimately Long Island Sound, he said.

“When you’re responsible for this whole plant…yeah, it can keep you up [at night],” Degnan said in a recent interview. “You can’t control Mother Nature… it’s beyond our control with the equipment that we have.”

Dennis Greci, an engineer with the Department of Energy and Environmental Protection, said the state is working closely with Stamford to resolve its issues, but not much can be done.

“Really, the contingency plan is basically having enough tankage in place. And they don’t,” he said, referring to the capacity of the tanks at Stamford’s sewage treatment plant. At issue is one of the plant’s secondary clarifiers, a large tank which is supposed to remove heavy solids from sewage. The tank is still in the midst of repairs after months of being out of commission.

“Some of this has taken close to a year to repair, and that’s really unacceptable,” Greci said.

Greci said his agency also has its eye on the treatment plant in Middletown, where 44 million gallons of partially-treated sewage spilled into the Connecticut Riverin the aftermath of Tropical Storm Irene. It took more than two weeks to stop the flow. The plant will eventually be abandoned and tied into a new treatment facility in Cromwell, but that won’t happen for another three to five years.

In the meantime, “we’re sort of hoping we can hold that one together,” Greci said. Since 2009, more than 318 million gallons of either partially-treated or raw sewage have been released by the plant, due to a combination of extreme weather and infrastructure issues.

Greci said that when it comes to sewer treatment plants, the state has three primary worries in the event of extreme weather: power needs, infiltration and inflow, and flooding.

Almost all of the state’s plants have a backup generator in the event of a black-out, but most are designed to run for 48-72 hours — not the several-day span of time for which power was out in much of the state after last year’s Nor’easter. Three generators had to be replaced last year.

Infiltration and inflow occur when excess water seeps into the soil and enters the sewage systems through leaky pipes, or when rainwater enters sewer pipes rather than storm drains. That excess water adds to an already-taxed volume of material in the pipes.

Finally, if the sewer pipes are flooded, there’s little to stop sewage from escaping the pipes. “Localized flooding itself, besides the infiltration and inflow issue, can actually lead to sewage escaping from the system,” Greci said.

Dozens of plants across the state will face challenges if the hurricane hits. Bridgeport has already released more than 100 million gallons of partially-treated or raw sewage into Long Island Sound this year, mostly due to heavy rain conditions. But Bridgeport has also been very diligent about reporting sewage bypasses, Greci said, while other cities may not be — so there may be issues the state isn’t even aware of.