New Haven Register (New Haven, CT)
Sewage overflows skyrocket all across Connecticut
Beyond the destruction of floods seen with the historic rainfall events Connecticut has recently faced is a filthy side effect: Each downpour has caused dozens of sewers to overflow and spreads harmful bacteria far and wide.
On Wednesday night, when Connecticut had its first-ever flash flood emergency from the National Weather Service, the results were historic: Stamford, Seymour, Clinton and the village of Uncasville recorded more than eight inches of rain. All that rain fell from the aftershocks of Hurricane Ida, which made landfall more than 1,000 miles away from Connecticut, in Louisiana.
The hurricane's rains came just a week and a half after the effects of a different tropical storm, Henri, which dumped up to five inches of water on the state.
These events are just the latest in a year that has so far seen more heavy rainfall events than usual. While climate change can’t be linked for just one storm, Connecticut, and the rest of the country, is facing a reality of more frequent weather extremes.
Those extremes can overwhelm some of Con
necticut’s aging infrastructure, adding urgency to long-promised updates.
Nine months into 2021, Connecticut has recorded 817 instances of sewage overflows, up by 73 percent compared to the same time last year, according to an analysis of live data from the state Department of Energy and Environmental Protection.
These types of overflows happen where outdated infrastructure still exists in six Connecticut municipalities: Bridgeport, Hartford, New Haven, Norwalk, Norwich, and Waterbury. “Combined sewers,” as they’re called, store runoff as well as sewage from homes and businesses in the same system. But these systems and the connected treatment facilities can become overwhelmed when it rains, sending a backflow of wastewater into the state’s harbors and rivers.
DEEP warned of the untreated sewage in the waters and advised all of the state's residents to avoid swimming, fishing and paddling following the
Wednesday night deluge, especially close to more urban areas.
But the environmental impact is more profound than a canceled beach jaunt or trip down one of the state’s rivers.
Kelsey Wentling, the river steward with the Connecticut River Conservancy, explained the flow of sewage into waters adds nitrogen and phosphorus, starting a chain reaction that has profound effects on wildlife. Certain plants, like algae and hydrilla, feed off the nutrients from the sewage and crowd out other species, both plant and animal, in part because they are using up more of the water’s oxygen.
“We are seeing an increase in the frequency and intensity of these occurrences,” she said. “That will probably continue.”
The overflows are happening despite years of progress toward improving the infrastructure built to contain the extra water. In late May, the Environmental Protection Agency lauded the states of New York and Connecticut on their progress, attributing lower levels of dissolved
oxygen and nitrogen in the Long Island Sound to years of work on wastewater management. The EPA cited a University of Connecticut study that concluded $2.5 billion in investments to improve wastewater treatment mean roughly 47 million fewer pounds of nitrogen flows into the Long Island Sound annually compared to the early 1990s.
Mark Tedesco, director of the EPA's Long Island Sound office, said in a statement the available readings from the sound show healthy levels of dissolved oxygen as of early Friday morning. Tedesco said the recent increase in sewage releases into the sound "are not contributing to a Soundwide problem," but conditions elsewhere could have seen different impacts. In the Long Island Sound's case, Tedesco said, the drop in water temperatures by September help the oxygen-rich surface waters mix with more oxygen-deprived bottom waters.
Wentling said smaller bodies of water are more susceptible. For instance, the Shetucket River in Norwich has taken in
about three times the number of overflows this year compared to the New Haven Harbor, DEEP data shows.
July was especially rainy, with every Connecticut county except New London experiencing at least double the normal amounts of rainfall during the month, according to the National Weather Service.
Peter Linderoth, director of water quality for Long Island-focused Save the Sound, noted the wastewater carries not only bacteria like E. coli but other pathogens dangerous to human health as well.
“The intensity and more frequent occurrences of these storms is concerning, and it's going to be very important for our elected officials to really start upgrading infrastructure with an eye towards these more intense and more frequent storms,” Linderoth said.
Save the Sound has been just one environmental advocate to point out many municipalities are decades behind on their obligations to upgrade outdated infrastructure that allows the overflows to happen.
It is also hard to judge the full magnitude of the overflows this year because utilities don't always note the estimated amounts in their reports to the state environmental agency. A spokesman for DEEP said they are working toward improving their data collection so that utility operators can't submit their required reports to the agency without estimating the volume of the overflow.
But so far this year, DEEP has recorded nearly 60 of the events where 1 million gallons or more of wastewater flowed into one of Connecticut’s waterways. That’s the most of any of the last five years, though again, the information is incomplete.
Half of those recorded events happened at the Metropolitan District, the Hartford area's water and sewer utility.
Nick Salemi, spokesperson for the Metropolitan District, said the water authority has cut back the volume of wastewater overflows by half in the last 15 years through its ongoing upgrades worth $1.6 billion. But threequarters through 2021, the Metropolitan District has
already reported the same number of overflows than it did in all of 2020, according to DEEP data. Unexpected heavy rains this summer are to blame, Salemi said.
"At some point if you get six inches of rain in four or five hours, there's just no system designed to take that," he said.
A massive construction project underneath Hartford will help to further remediate the problem. A four-mile long tunnel will be able to contain 41.5 million gallons of water so that the utility can treat it before releasing it into the Connecticut River. The tunnel is projected to be finished by 2023.
A state-specific report from the University of Connecticut predicts instances of "extreme precipitation" will continue to increase through 2050 as a result of climate change, and found little likelihood that anything done in the near future could reverse that reality given the damage already done.
But, the researchers noted, human choices can reverse the course and impact what happens in the second half of the century.