CT shoreline towns that will be under water in Category 3 hurricane

This FloodIQ.com map shows where flooding would occur in Greenwich 2034 in a Category 3 hurricane. FloodIQ.com provides a searchable tool shows how communities large and small, from This FloodIQ.com map shows where flooding would occur in Greenwich 2034 in a Category 3 hurricane. FloodIQ.com provides a searchable tool shows how communities large and small, from Photo: / Photo: / Image 1 of / 36 Caption Close CT shoreline towns that will be under water in Category 3 hurricane 1 / 36 Back to Gallery

Each year, there are new studies projecting the effect rising sea levels could have on shoreline communities.

The combination of rising sea level and a powerful Category 3 hurricane could be catastrophic.

Now, there’s an online map that provides graphic, visual evidence of threats to Connecticut's shoreline communities as sea level rises.

FloodIQ.com provides a searchable tool that shows how communities, from Greenwich to Stonington, face greater risk of tidal flooding and storm surges over the next 15 years.

Using data from sources such as NOAA, USGS, and NWS, the map details overall impacts on property values, the number of individual residential and commercial properties at risk and the number of community facilities at risk.

Communities identified as “at risk” include the shoreline municipalities of Bridgeport, East Haven, Groton, Guilford, Mystic, New Haven, New London, Southport, Stamford, Greenwich, Stonington, West Haven, and Westport. Municipalities along tidal rivers, such as Shelton and North Haven, are also identified as “at risk.”

Communities further upstream along tidal rivers, including Middletown and Hartford, are identified as having “minimal risk,” but are warned that risk “will worsen as sea levels continue to rise” beyond the tool's 15-year time frame.

FloodIQ was developed by First Street Foundation, a nonprofit that “quantifies and communicates the increasing risks associated with sea level rise.”

Connecticut has not been hit by a hurricane or tropical storm since Irene and Sandy in 2011 and 2012 hit the shoreline.

Lending increased urgency to the issue of Connecticut’s shoreline vulnerability was the release last November of the National Climate Assessment that, among other things, details how more intense precipitation and increasing sea level rise threaten the northeast.

NOAA’s 2017 State of U.S. High Tide Flooding Report and 2018 Outlook found that three of the top five cities with the highest number of flood days, and which broke records, were Boston, Atlantic City, and Sandy Hook in New Jersey. Connecticut is right in the middle of them. For places like the Long Wharf area of New Haven, built on fill in what was once a harbor, the end game could be catastrophic.

NOAA’s prediction is that when this meteorological year ends in April 2019, high tide flooding will be 60 percent higher than it was 20 years ago and double what it was 30 years ago.

NOAA determined that by 2045 there will be about 4,500 homes at risk just of chronic inundation. Those homes are currently valued at nearly $3.5 billion and contribute more than $52 million in terms of property taxes. By the end of the century, with a high sea level rise scenario, Connecticut would be looking at about 25,000 homes at risk with a value of nearly $15.5 billion and property taxes of more than $252 billion.

Fairfield tops the list for both number of properties impacted and their value.

Previous reporting by the CTMIRROR.ORG was used in this story.