Traumatic disasters can also linger in the minds of the afflicted. "We shouldn't forget about mental health issues. Disruption or not having access to your local support system can have serious consequences for mental health," Kinney said. "That was documented fairly well after [Hurricane] Katrina."
However, New York is not New Orleans. Compared to the Louisiana bayou or the Florida wetlands, Gotham's concrete jungle reacts a bit differently to high water levels. "The impervious surfaces that are characteristic of urban areas prevent some of the natural buffeting that natural coastlines can provide when a storm hits," Kinney said. He observed that Staten Island faced some of the most severe flooding in Sandy's wake, largely because concrete now coats the borough's wetlands.
The standing water can then overwhelm the city's sanitation services, which end up dumping raw sewage into the Hudson and East Rivers. Pooled water also leaches and mobilizes toxic compounds in streets and soils, Kinney added.
New York City's size and scale also exacerbate problems less populated regions could shrug off. "You have a lot more people in harm's way," Kinney said.
Health care facilities also suffered from the storm. "New York City, as we learned from Sandy, has a lot of its critical infrastructure along the coast," said Radley Horton, an associate research scientist at Columbia's Earth Institute. Scenic views of the rivers put the hospitals at greater risk for flood damage, as the storm made abundantly clear last week.
Hospitals among the victims
New York University's Langone Medical Center near the East River saw both of its backup generators fail from flooding. The same thing happened at Palisades Medical Center in New Jersey. As of yesterday, officials evacuated Bellevue, Langone, Manhattan VA and Coney Island Hospitals due to systems failures. Beth Israel Hospital regained power recently after running on a generator following the storm.
Without power, hospitals cannot keep ventilators, drug pumps and dialysis machines running. Their computers also need to stay online to track patients, keep inventory and dispense medications.
Under a changing climate, these problems will only get worse. "New York City has experienced about a foot of sea-level rise over the last century. Under conservative estimates, we expect to see 2 feet [of sea-level rise] over the next century," said Horton. "We expect coastal flooding events happening three times as often."
But hurricanes have exacted heavy tolls before, and hospital backup generators failed in New Orleans after Katrina and in Connecticut after Hurricane Irene. Given New York City's vulnerability to flooding and lessons from past storms, should planners have seen these problems coming, and could they have made better choices?
"When you look back at an event, it's always easy to identify things you should have recognized," said Henry Willis, acting director of the RAND Homeland Security and Defense Center. "We do need, as we plan out infrastructure and risks, to consider what the risks to the infrastructure are going to be."
To handle rising sea levels and increasingly destructive disasters, officials need to consider all of the ways they can reduce risk, according to Willis. This includes big infrastructure projects to control floods, like levees and breakwaters; retrofitting individual homes or moving homeowners away from floodplains; and restoring wetlands to serve as natural water sinks.
"The choice you make in a plan like that requires setting priorities among what people value most," Willis said. Regional planners need to decide issues like whether they value coastal real estate above all else or the integrity of the environment, or whether they are willing to pay the costs up front or over time.