As officials assess the damage Hurricane Ian caused in Florida as a Category 4 storm,researchers at Harvard are warning that even less powerful hurricanes pose a serious flood risk to hospitals in coastal cities, including Boston.

A Harvard T.H. Chan School of Public Health report released today says nearly a quarter of hospital beds in Boston would be at risk in the event of a Category 2 hurricane. Out of nearly 80 coastal cities included in the study, Boston was ranked third for most vulnerable to potential impacts, behind the Miami and New York metro areas.

"Our metro area actually has relatively fewer beds available — hospital beds — per population served," said the study's senior author Dr. Aaron Bernstein. "And so that means that even though the bite of the hurricane out of the pie of healthcare may be smaller [than other cities], we didn't have as many beds to start with."

The study's authors say their research should serve as a warning to coastal hospitals that they must act now to make their operations more resilient to the growing threat of hurricanes, both by making their infrastructure more resilient to storms and by working together to develop plans for a coordinated response when hurricanes strike. Boston area hospitals tell GBH News they're working on it.

Of course, Boston isn't at the same level of hurricane risk as the Florida communities battered by Hurricane Ian.

"We may not see one for a while," said Bernstein, interim director of the Center for Climate, Health and the Global Environment at Harvard T.H. Chan School of Public Health. "But let's be clear, we see hurricanes here ... [and] hurricane tracks are quite clearly moving northward. This is a trend that has been well documented. It's very consistent with what we see from the warming of the oceans due to climate change."

And, Bernstein noted, with the sea level rise expected this century, models suggest a more than 90% increase in the number of Boston-area hospital beds at risk of flooding from a Category 2 storm. The laststorm of that size to hit Massachusetts was Hurricane Bob, in 1991.

The report, which was published in the journal GeoHealth, studied 78 Atlantic and Gulf Coast metro areas. Researchers found that in 25 of those regions, more than half of hospitals would be at risk of flooding from a Category 2 storm.

Even a Category 1 storm would cause flooding at Cape Cod Hospital, Good Samaritan Medical Center, Martha's Vineyard Hospital, Massachusetts General Hospital, Mount Auburn Hospital and the Tobey Hospital Campus of Southcoast Hospitals Group, according to the report. In addition to those hospitals, the study's authors say a Category 2 hurricane would flood Tufts Medical Center and the Cambridge campus of Cambridge Health Alliance.

The study says a Category 2 hurricane would also flood more than 14% of roads within a mile of Boston-area hospitals, making it challenging for people in those areas to access care during a storm.

Explore the map to see flood risk based on storm severity at hospitals in Greater Boston, the Cape and Islands.

Bernstein said while strengthening hospital infrastructure against flooding is important, more systemic coordination is needed to prevent storms from turning into crises for hospitals.

"We can't do resilience by simply focusing on what's within the four walls of the building," he said. "We absolutely need coordinated responses that account for whether we're going to be able to move people and supplies, where there are beds that are the appropriate acuity, where's the expertise. And beyond that, we should be doing a lot before hurricanes happen, especially for people with chronic medical problems who need regular access to care and where their primary point of access is almost certainly going to be compromised by a hurricane."

Some Boston-area hospital say they've been concerned about this for years, and they continue to reassess their emergency plans.

At Tufts Medical Center, Nick Duncan, the director of operations and emergency management, said they have a plan in place to meet the requirements of the so-called"96 hour rule" — a standard of theJoint Commission, which does accreditation for hospitals.

"Do we have enough food in the house to make sure we can survive on our own? Do we have enough water — both non-potable for boiling and also for like toilet flushing, but also drinking water for our patients and staff?" Duncan said of the plan. "Do we have enough diesel generator fluid and all those types of things? So that's kind of ingrained into every emergency manager's brain when we start thinking about what we need to have on site and what we need to be able to get our fingertips on pretty quickly."

Josh Baugh, medical director for the emergency department at Massachusetts General Hospital and medical director for emergency preparedness, said MGH is "well positioned" because people have been thinking about possible storm impacts for years.

"And I would say, emergency preparedness is kind of a continuous process. You can always be more ready," he said. "And I think that we can still be more ready."

"Emergency preparedness is kind of a continuous process. You can always be more ready."
Josh Baugh

Baugh said MGH has been looking at future projections for storms and making sure hospital facilities can handle what's coming.

"Things like thinking about the height of floodwalls and where you put different components, and what's low and what's high. What's potentially protected from water, what's not. Making sure that building facades and infrastructure is ready for different levels of wind speed. Making sure that everything's rain-proof."

Baugh acknowledged it would be a challenge for Boston hospitals to evacuate patients, if that ever became necessary. But he said the 12 hospitals that are part of the Conference of Boston Teaching Hospitals have been focused on this possibility.

"We come together multiple times a year to focus on different emergency preparedness priorities," Baugh said. "And evacuation, actually, is one of the ones that's being talked about most this year. And so fortunately, there is collaboration between all the hospitals talking about what are our different plans for this. And if one hospital ran into trouble, it's a good platform to be able to talk about how do we get patients between them, and what is our overall holistic plan for for the city."

Baugh noted that Massachusetts is also part of a federally funded partnership called the Regional Disaster Health Response System, which connects hospitals across New England for disaster planning.

Baugh said MGH has studied the impacts on hospitals when other cities, like New Orleans and Houston, have been clobbered by hurricanes. And now, they're watching what happens in Florida.

Bernstein, the new study's author, said that's exactly what needs to happen.

"The helpful part here is that hurricanes aren't new," Bernstein said. "There are communities that have real experience that is enormously valuable that we can learn from. And my hope is that we can trust science here, that we can see these problems coming."

A lot is already known, he said, about ways to make hospital operations more resilient in hurricanes. And the risk is continuing to grow.

"So I think it behooves us to really get ahead of this," he said. "And I'm hopeful that our work will help give a little more knowledge that will push us to do a little better to that end."