Photo: NBC Connecticut

By Tricia Ennis, February 19, 2023, CT Insider

Ten years ago, Super Storm Sandy slammed into the East Coast, damaging homes, flooding neighborhoods, and knocking out critical infrastructure across New York, New Jersey, and Connecticut. Ten-foot storm surges pushed coastal waters onto the shores of Long Island Sound, even though the storm hit at low tide, and high winds toppled trees across the state. In the aftermath, the state of Connecticut allocated $5.4 billion of Community Development Block Grant funds to help rebuild.

The storm might have been less damaging if it weren’t for increased sea levels, which contributed to larger coastal flooding. According to a 2021 study from Climate Central, approximately $8.1 billion of the reported $60 billion in damages from the storm were attributable to sea level rise from climate change. They also found that the rise contributed to flooding further inland, affecting approximately 71,000 additional people.

The study analyzed the total impact of the record-breaking storm and compared it to two separate models that estimated how much of that damage was caused by the increase in sea levels over the last century. The researchers called the study the first to calculate the real costs of human-caused sea level rise, which they estimate to account for just over half of the total rise in sea level.

As towns and cities look to the future, there is a deep history and an increasing sense of urgency to act.

In Connecticut, around 61% of the state’s population lives in an area threatened by coastal flooding. Projections provided by the Connecticut Department of Energy and Environmental Protection (DEEP) show that the state is at risk of losing up to 24,000 acres of land to rising sea levels in the next 50 years.

But these are not new concerns. In 1968, the federal government passed the National Flood Insurance Act, making the policies available to homeowners for the first time. The move was a response to the damage left in Florida and Louisiana after Hurricane Betsy in 1965. The act established the National Flood Insurance Program, a federal insurance program that offers low-cost flood insurance to homeowners in flood zones.

The idea was simple. Flood and storm damage is costly and the Federal Emergency Management Agency (FEMA) often had to foot the bill to help homeowners adversely affected by disasters. Affordable flood insurance could offset those costs for homeowners and the government.

In 1973, the Flood Insurance Protection Act made it mandatory for homeowners with federally backed mortgages to purchase flood insurance if their home sat within one of the flood risk zones.

Four years later, in 1977, flooding became a priority here in Connecticut. That year, Governor Ella Grasso signed Executive Order 18, which included several mandates for state agencies. It directed state agencies to lessen the risk of flood loss connected to state lands and installations, made it so agencies responsible for administering grant and loan programs did so without “uneconomic, hazardous, or unnecessary use of floodplains,” and stated that all agencies with programs affecting land use planned “shall encourage land use appropriate to the degree of hazard.”

Of primary concern for Connecticut is flooding along the coastline, which makes up the entire southern border of the state. The areas closest to the ocean, naturally, present the greatest risk of flooding due to storm surges and abnormally high tides. As a result, cities and towns in these areas face an increasing threat of flood damage due to multiple factors.

“Along the shoreline, there have been many towns where there were summer communities and they have become year-round communities; become very densely populated. That’s true from East to West along the shoreline,” explains Dr. James O’Donnell, Director of the Connecticut Institute for Resilience and Climate Adaption (CIRCA) at UConn. “And those towns were built in areas where there were natural harbors or fishing areas and the roads circumvent marshes. And over the last 100 years, sea levels have risen maybe 10 inches, and that means that those roads, and houses adjacent to them, are more prone to flooding than they were 100 years ago.”

CIRCA was started 10 years ago as part of an effort to provide cities and towns in the state with research-based advice for dealing with the effects of climate change. In that time, their work has only continued to expand to meet the broader needs of residents, focusing more these days on increasing climate resiliency. The team is made up of people from a variety of specialties, including marine science, urban planning, and law.

The CIRCA team works with lawmakers, local government policy directors, and city planners to design solutions that help protect the community from increased flood risk. They also help find funding for those projects. Currently, CIRCA has around 70 projects in the early stages of development and seven in the design and funding stages.

O’Donnell says one thing they have learned is that every town faces unique challenges that can’t be solved with one-size-fits-all solutions.

In many coastal cities and towns, he explains, the railway tracks are built quite low so roads passing beneath the tracks are slightly submerged, which causes them to flood during poor weather.

“The problem is now that’s happening more frequently too, and it disrupts normal business traffic,” he says. “But what’s worse, in the event of a real hurricane, those routes are often emergency evacuation routes. So, we’ve got two projects underway where we’re trying to design ways to reduce the flooding risk to those sites, so the roads would remain serviceable during normal storms and then during these severe events as well.”

O’Donnell says that people living and working along the coast face two main problems when it comes to coastal flooding: big storms and rising sea levels.

“There’s a small threat every year of a severe hurricane anywhere in Connecticut,” he says. “If that were to happen, then the storm surge could be 20 feet high. And much of the shoreline where that hurricane passed by, the buildings and roads and houses, would be severely damaged.”

O’Donnell says there isn’t very much that can be done to shore up communities against these massive storms.

“Our strategy for addressing that has been and will remain: evacuate everybody from the zone that’s likely to be impacted and when the hurricane is over, fix it up and come back, and that’s probably not gonna change,” he says.

To add insult to injury, major storms are becoming much more common. Connecticut has seen a reported 38% increase in the amount of precipitation annually, according to records from the National Oceanic and Atmospheric Administration (NOAA). In a survey of NOAA data from 2015, Climate Central found that Connecticut saw some of the largest increases in precipitation over the last 50 years, coming in fifth in the nation and third in the heavily impacted Northeast. Increased rainfall can contribute to both storm surges from severe weather events and to inland flooding along the state’s rivers and streams.

Since Hurricane Irene hit in 2011, the state has taken damage from five additional hurricanes and tropical storms.

“To protect an area from something like that you’d have to build seawalls that are really high,” explains O’Donnell. “That makes sense around things like water treatment plants and power stations, and perhaps hospitals and police buildings, etc, some services and critical infrastructure. And so we’ve been making sure that those facilities are resilient.”

Hurricanes and tropical storms, however, are big, headline-grabbing events. They happen infrequently but they take up most of the public’s attention when it comes to damage from flood waters. Sea level rise, meanwhile, presents a more subtle, more consistent threat.

According to O’Donnell, sea levels have increased around 10 inches in the last century, but they are projected to increase an additional 10 – and as much as 20 – in just the next 27 years. As sea levels increase, tides come closer to homes, businesses, and critical infrastructure along the shoreline, and smaller amounts of precipitation can lead to damaging flash floods. Events that used to happen once a decade could now happen as often as every two years, says O’Donnell.

“Just because the mean water level was higher, a thing that used to cause a little flooding is now gonna cause a lot more flooding,” he says.

Those floods aren’t as damaging as those caused by hurricanes, which is a double-edged sword. On the one hand, they are easier to prepare for, but on the other, they feel less urgent.

“If you want to protect yourself from the consequences of increased sea level,” says O’Donnell. “Then raising everything two feet would get you back to what the risk was a hundred years ago.”

Those fixes, though, are only temporary, since sea levels are projected to keep increasing. Increased carbon dioxide in the atmosphere has caused a warming of the Earth’s oceans, melting polar ice caps and causing the water already in the ocean to expand as it heats. Even if we stopped releasing greenhouse gases entirely tomorrow, it would be years before its effects stopped.

“When we stop pumping CO2 into the atmosphere, sea level is gonna continue to increase for a while,” says O’Donnell. “Because once it’s in the atmosphere, the heating continues, and the ice melting continues.”

The increasing risk of flooding isn’t just a concern for those living on the state’s coast.

“Connecticut industry in the 18th to 19th century evolved around rivers and streams, and so there’s lots of towns in Connecticut where there’s dense infrastructure around the mill or a dam and then there are housing areas adjacent to those,” says O’Donnell. “And all of those are vulnerable. Many areas are vulnerable to flooding in those rivers now, and that’s getting worse. We think because of the effects of climate change on the statistics of precipitation rates.”

Cities and towns along the state’s rivers and streams, especially places along something like the Connecticut River, face their own flooding challenges. Rivers and streams do naturally flood during times of increased precipitation but with an increase in the amount of heavy rainfall, that can happen more frequently.

Connecticut is also in a tough position geographically, as the southernmost state in New England. The state’s position at the bottom of major rivers, namely, the Connecticut River, means that Connecticut also sees an increased impact from snowmelt. As snow in places like Vermont and Massachusetts melts – perhaps during heavy rain – it is added to the river. The further down the river you are, the more of that water you see, meaning Connecticut isn’t just affected by weather events here, but in neighboring states as well.

Adding to this problem is the fact that urban development has historically made flooding problems worse due to the use of concrete and asphalt, which do not allow rainwater to naturally soak into the ground. Instead, these non-porous surfaces redirect that water into storm drains and directly into rivers and streams, contributing to both rising water levels and an increase in runoff of potentially hazardous substances.

“As we’re seeing these bigger, more frequent rain events, that’s really creating problems for how stormwater is being managed,” explains Nicole Davis, a watershed developer at Save the Sound. Davis and Save the Sound work to find ways for cities and towns in the state to counter these manmade flooding issues, methods that allow urban developers and property owners to create structures that return land to a more natural state while disrupting human spaces as little as possible.

“There’s a lot of stormwater that’s not — it’s going straight into our rivers rather than having a chance to go into the ground,” she continues. “And so, the way that we’re kind of thinking about addressing that is how do we get people to start thinking about that impact that what they’re doing has? ’cause everything on people’s lawns, especially in coastal areas where you’ve got flooding, anything on the road, they all get washed into our storm drain, they all end up in the rivers and streams that we’re swimming in.”

Hartford has a long history of flooding along the Connecticut River. Measurable flooding on the state’s largest inland waterway has been happening as long as we’ve kept records and back in 1936, the city experienced what is described as “The Perfect Flood.” Thirteen days of rain caused severe conditions across the state, and in Hartford, it culminated with the river nearly 40 feet higher than average. Thousands were forced out of their homes.

Hurricane Connie, in 1955, killed 87 people statewide, many of them in inland cities like Waterbury, where the death toll was 29.

To combat river flooding, Hartford has spent decades investing in the Hartford Local Protection Project which protects approximately 3,000 acres of the city, including the most densely populated city center. The project consists of thousands of feet of “dikes, floodwalls, stoplog structures, conduits, and pumping stations.”

The project began in 1938 and was completed in 1981 at a total pricetag of $71.5 million.

For Davis, the solution to the state’s growing flood problems is simple in concept and complex in execution. There are concrete ways to mitigate certain types of flooding, but they will not solve the whole problem at once and will take a lot of work – and money — to implement across the board.

For one thing, flooding is an issue that, if it doesn’t directly or regularly affect you, can be easy to overlook. For Bill Lucey, Soundkeeper at Save the Sound, and someone who works directly with state policymakers to provide information and find funding for projects, it’s all a matter of perspective.

“If you’re flooding every high tide, you’re noticing it,” he says. “If you’re almost flooding every high tide, maybe you’re noticing it, and if you’re 20 years out from being in that situation — even though the models are projecting that your area is gonna flood on a high tide in 20 years — it’s hard to get people focused on it.”

“Some people notice it, some people don’t, and some people don’t want to notice it,” he adds.

Are there marketing efforts underway to fix the awareness problem?

“It’s the people who, their basements flood or their properties are flooding, they see it all the time, and so they can’t not notice it,” Davis agrees. “But for other people, the rain goes away and the flood waters recede, so it’s not necessarily in the forefront of their thinking anymore.”

Lucey says there is one time when everyone starts paying attention, and that’s after massive storms that impact a large number of people, whether through inconvenience, damage to property, or loss of life.

“I think strategically, it’s after these big disasters that we really end up making big policy moves,” says Lucey. “That we end up passing big bills, and we end up putting larger amounts of funding to support the work that Nicole and her team are doing to try and put solutions on the ground, but it’s definitely a matter of perspective.”

As evidenced by the dozens of projects on CIRCA’s radar these days, municipal leaders are thinking about what their towns can do to mitigate the damage done by floodwater, but actual plans must be adapted to the challenges of each city and town individually.

“We have a built environment and we’re not gonna change that, we’re not gonna tear down all these houses on a sand spit and create it back to a marsh habitat, just is not realistic,” explains Davis. “So how do we work within our urban environment to make sure that it’s functioning to the best of its ability and not just business as usual? Because that’s how we’ve always done things.”

In Bridgeport, city leaders, with help from CIRCA, have begun implementing projects aimed at increasing the number of pervious surfaces spread throughout some of the areas most often affected by flooding.

Bridgeport Sustainability Director Chadwick Schroeder says their engineering department is focusing on removing some of the more impervious surfaces, replacing them with sidewalks made of old tires, and adding rain gardens to manage stormwater. They’re also looking into increasing the number of green spaces in the city, turning them into parks that can hold water while also adding habitats for pollinators and urban canopy.

For Schroder, any improvements made for the purpose of sustainability must serve more than one purpose and must serve the needs of multiple communities.

“How can our projects build on needs? Environmental and economic,” he explains. “There are numerous places in the city where all those needs interact.”

In New Haven, the folks at Save the Sound have begun working with the local water pollution control authority to offset problems caused by the city’s combined sewer system. In a combined system, all the water flowing from home plumbing gets combined with water flowing into street-level storm drains, which flows through to the local water treatment plant. During dry weather, this works as intended, but with heavy rainfall, the system can overflow.

“What that means, when it overflows, is that sanitary waste — everything that’s coming from your sinks, your toilets, your bathtubs — are going into the rivers untreated along with the stormwater,” explains Davis. “So the water purification control authority — several across the nation — have started to embrace this idea that how do we put less stormwater to our combined systems to help kind of change that tipping point during a rain event.”

Among the solutions they’ve been working on is the installation of bioswales, channels near roadways that are designed to capture and absorb rainwater runoff before it hits the sewer system. According to Davis, New Haven has already installed hundreds of bioswales to help ease the burden on the combined sewer and to combat localized flooding.

Then, there is a question of whether some structures can be converted to less impervious options. Davis provides the example of a beach area in Long Island where they were able to convert impervious parking lots into more absorbent alternatives while converting another into open grassland that could be used as overflow parking when needed.

Back in New Haven, Davis says they’ve worked with the city to convert a small, abandoned, dead-end roadway next to an elementary in the Fair Haven district into a small green infrastructure park.

“It was just an abandoned dead-end roadway that had been used as a dumping ground. There was no value to it from a functional roadway standpoint or from the community standpoint, it was really used as a garbage dump by people outside of the neighborhood,” explains Davis. “We identified the site as something that had a lot of potential — both for ecological function and stormwater function — but then also kind of balancing this idea around human needs. We’ve got to make the space accessible and friendly. Nobody wants to be told what to do, but when you make something that’s functional for a community into something that can also function from a climate resilience perspective, it’s got a lot of wins.”

Multi-use parks seem to be the name of the game when it comes to resiliency planning. It might be difficult to convince a town that they need to convert already developed land into something more climate-friendly, but when you combine it with beautification projects, or an increase in local parks, it can be an easier sell.

While local cities and towns will have to come up with individualized solutions to their very specific local problems, leaders agree that doing nothing isn’t an option.

“If we’re not addressing localized flooding, we’re losing places to live,” says Davis. “And if we’re not protecting our shorelines, the same thing is happening.”

But a property owner’sability to deal with the effects of increased flooding is, in many ways, dependent on their financial means. Wealthier individuals and families can afford to make costly improvements, like elevating their homes above sea level or moving further inland, more easily than those of lesser means.

“They’re not seeing the impacts quite as significantly as those who, this is where they live, this is where their family lives, and they don’t necessarily have the resources to change that up or to make large modifications to their home,” says Davis. “So, we have that humanitarian quality of life issue.”

A move further inland – something referred to on a larger scale as climate migration – brings with it its own problems, like potentially increased housing costs.“What may happen is places that are a little farther inland, not subject to flooding are gonna look more attractive,” says O’Donnell. “And so property values in areas which are close to the shore but don’t get flooded and don’t have to replace their heater every five years or pay high flood insurance rates, they’re gonna become more popular.”

A 2020 study published in Environmental Research Letters identified Connecticut as one of the top 10 states in the country where affordable housing is at risk of flood damage from sea level rise. That projected risk increases by 2050, when an estimated average of 695 affordable housing units will be at risk of flooding each year. That’s nearly double what the risk was in 2000 and still amounts to only a fraction of the total number of properties at risk of yearly flooding.

Connecticut already faces a housing shortage which has pushed home prices and rents higher than average residents can afford. An influx of residents moving away from the coastline to escape flooding would only add to the problem.

“It’s a race,” says Lucey. “It’s a race between how much infrastructure damage, how much ecosystem damage are you’re gonna absorb, versus how much are you gonna spend to prevent that damage from occurring in the first place?”