Some Connecticut hospitals at risk of flooding in hurricanes, study shows

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Hurricane Ian, Sept. 29, 2022.

Hurricane Ian, Sept. 29, 2022.

National Hurricane Center

A new study that investigates the flooding risks to hospitals within a mile of the Atlantic and Gulf Coasts during category 1-4 storms highlights concerns with at least a few facilities along Connecticut's shoreline.

The study, conducted by the Harvard School of Public Health and Boston University, found that even weak storms pose a severe risk of flooding to certain hospitals even without sea level rise. As expected, flood risks increase with a projected sea level rise of 2.6 feet increase the vulnerability of hospitals up and down the coast to storm surges, even for “mild” storms.

In Connecticut the two most at-risk hospitals are Milford Hospital which is projected to suffer flooding from storm surges during a category 3 hurricane. Yale New Haven Hospital is projected to be at risk with 2.6 feet of sea level rise.

"I think our study is a call to action to hospitals," said study author Dr. Alexandra Gast, a professor of family medicine Boston University School of Medicine. "Figure out ways to learn from events that have already happened and protect their care of patients."

The study was released as Hurricane Ian and its storm surge flooded communities across Florida, knocking out power and may wind up as the "deadliest hurricane in Florida's history," President Joe Biden said.

While New England as a region is no stranger to severe storms, full-on hurricanes have been more rare. Instead, the area has faced multiple tropical storms in the last two decades. But as human-caused climate change progresses storms, including hurricanes are expected to increase in frequency and severity.

“We now have a better sense of which hospitals are likely to flood from a hurricane today and those that need to prepare for greater risks in the future,” said senior author Dr. Aaron Bernstein, interim director of the Harvard  School of Public Health's climate change center. “Hurricanes are expected to get more severe and may strike regions further north than in the past due to climate change. In places like my hometown of Boston, we can avoid crises that other hospitals have had to endure by learning from their experience and creating plans that build on best practices. But we must act now, before disaster strikes.” 

According to the study, Connecticut is fairly well-positioned relative to its neighbors. The most at-risk hospitals nearby are located in the Boston and New York metro areas.

"I would say the risk of flooding is greater in some of the surrounding states like Massachusetts and New York," said Gast. "Those rose to the top as having outsized impact."

However this does not mean Connecticut’s hospitals are invulnerable. Gast explained that the study also examined the impact of storm surges on road flooding near the hospitals. Of the 10 coastal hospital surveyed, four hospitals, Milford Hospital, Lawrence & Memorial in New London, Stamford Hospital, and Norwalk Hospital are at risk of losing over 10% of surrounding roads due to flooding.

Jordan Swenson, the disaster preparation manager of Yale New Haven Hospital, said that since Super Storm Sandy in 2012 hospitals up and down the coast had gotten much better about preparing for and coordinating in the event of storms. Hospitals across the state and region are on regular calls to coordinate in the event of weather emergencies.

"Because of Sandy, we've increased those conversations," said Swenson. She explained that hospitals and skilled nursing facilities had pre-existing arrangements for patients in the event of adverse weather. Swenson said that Yale New Haven Hospital, internally, had moved all their emergency backup generators out of the basements in response to seeing flooded generators in New Orleans hospitals during Hurricane Katrina.

"Moving forward we are looking at continuing to mitigate by upgrading those generators, equipment that we purchase and infrastructure that we're building," she said.

When asked about the implications of the study specifically on the Yale New Haven and Milford hospitals Swenson was cautious. 

"I have not seen a combined sea level rise and category three storm map," said Swenson. "That's not to say we aren't worried. Based on the (FEMA and NOAA flooding) maps we will not see flooding however we will definitely see, because of high wind and high rain in proximity to the shore, we will definitely see water intrusions, leaks, and those will probably impact patient care."

The study has several limitations. Gast explained that the models only accounted for possible storm surges and did not include rain. That’s potentially problematic for estimating flood risk as storm surge waters are only part of the equation. Low lying hospitals not at risk for storm surge may be at risk for a storm surge if it is combined with high rainfalls. In addition, the study did not assess the risk of floodwater on infrastructure function like drinking water, sewage and electricity which would also impact hospital function.

Gast asks that each hospital reviews their infrastructure and emergency procedures to harden themselves for the worst-case scenario. What that means is different for each hospital. Some will probably have to elevate patient care to higher floors. Others may have to move emergency backup generators out of their basements. Some may have to invest in additional flood mitigation infrastructure. 

"It's a really important topic and I don't think it's discussed enough because honestly the future is unknown" said Swenson. She emphasized that in spite of the uncertainty that the hospital system trying to plan for the worst. "I don't think we're planning based on the assumption that we'll see an increase in storms. Regardless I think we are prepared whether we have one storm or we have ten."