East Coast States Are More at Risk of Coastal Flooding Than West Coast States
Chloe Della Costa is a freelance copy editor and writer with a degree from Bard College. She specializes in copy editing and fact-checking content related to personal finance, insurance, and business.
Coastal flooding can pose a significant threat to communities across the U.S., particularly as sea levels rise and extreme events become more intense. Not only can coastal flooding be devastating in and of itself, but the coastal erosion it causes creates more threats.
LendingTree examined which coastal states are most at risk of coastal flooding and how coastal flood events have changed over time. Additionally, learn how to use your homeowners insurance to prepare for coastal flooding.
Key findings
- New Jersey is the coastal state most at risk of coastal flooding. Across the three flood risk categories we analyzed — exposure area to coastal flooding risk, expected annual building value loss and expected annual population equivalence loss — New Jersey ranks at least fourth. Notably, the state has the highest expected annual building value loss at $605.3 million. That’s almost nine times higher than the second highest-ranking state in this category, Virginia, at $67.7 million.
- Florida has the highest number of square miles exposed to coastal flooding. Florida has 758.0 square miles potentially exposed to coastal flooding — substantially higher than the next state, Louisiana, at 429.1 square miles. Four other states have 100 or more at-risk square miles: Texas (201.3), New Jersey (117.4), South Carolina (108.5) and North Carolina (104.9).
- Washington has the highest expected population equivalence loss due to coastal flooding. Washington has an expected economic loss of $34.8 million annually due to coastal flooding fatalities and injuries. New York ($33.0 million), New Jersey ($28.8 million) and Oregon ($10.0 million) follow.
- Looking at coastal weather stations, 21 of the 33 sites analyzed saw coastal flood events double or more between 1990-2009 and 2010-2022. Mayport, Fla. (771.8%), saw the biggest increase in coastal flooding events, followed by Wilmington, N.C. (583.8%), and Charleston, S.C. (464.1%). Only two of the 33 sites analyzed experienced a decrease in coastal flooding events between the two periods: San Francisco (89.0%) and La Jolla, Calif. (21.0%).
How did we determine coastal flooding risk?
To determine the coastal states most at risk of coastal flooding, researchers analyzed three Federal Emergency Management Agency (FEMA) National Risk Index (NRI) data points to create composite scores in which each was weighted equally:
- The area in each state (measured by square miles) exposed to coastal flooding risks
- The expected annual loss in building value (expressed in dollars) due to coastal flooding
- The expected population equivalence loss (measured in fatalities and injuries and expressed in dollars) due to coastal flooding
We created separate composites for coastal states with ocean coastlines and those with Great Lakes coastlines (plus the District of Columbia). New York has ocean and Great Lakes coastlines but was included only in our ocean analysis. Minnesota had no expected annual losses listed and was excluded from the Great Lakes analysis.
Separately, researchers analyzed U.S. Environmental Protection Agency (EPA) coastal flooding events data from 33 sites along the U.S. coast. We calculated the change in coastal flood events from 1990-2009 to 2010-2022 — periods preset by the EPA.
Among coastal states, New Jersey has the highest risk of coastal flooding
New Jersey is the coastal state (with an ocean coastline) most at risk for coastal flooding. The Garden State has the highest expected annual building value loss at $605.3 million. That’s significantly higher than the second-highest-ranking state in this category, Virginia, at $67.7 million.
Additionally, New Jersey has the third-highest expected annual population equivalence loss and the fourth-highest number of square miles exposed to coastal flooding.
Coastal states most at risk of coastal flooding
| Rank | State | Area exposed to coastal flooding risk (square miles) | Expected annual building value loss | Expected annual population equivalence loss |
|---|---|---|---|---|
| 1 | New Jersey | 117.4 | $605,270,786 | $28,769,710 |
| 2 | New York | 68.5 | $58,504,339 | $33,011,662 |
| 3 | Louisiana | 429.1 | $56,267,800 | $2,145,380 |
| 4 | Florida | 758.0 | $30,182,254 | $5,908,349 |
| 5 | Virginia | 76.2 | $67,731,096 | $3,308,596 |
| 6 | Texas | 201.3 | $43,033,621 | $395,928 |
| 7 | Washington | 29.9 | $17,964,123 | $34,791,375 |
| 8 | Maryland | 37.6 | $38,334,655 | $898,253 |
| 9 | Oregon | 8.3 | $33,558,047 | $10,046,530 |
| 10 | Connecticut | 27.6 | $17,598,184 | $6,404,066 |
| 10 | South Carolina | 108.5 | $4,285,987 | $1,308,813 |
| 12 | North Carolina | 104.9 | $8,075,865 | $699,447 |
| 13 | Massachusetts | 47.5 | $17,931,806 | $351,740 |
| 14 | California | 60.1 | $13,401,295 | $244,161 |
| 15 | Delaware | 20.7 | $22,787,351 | $311,437 |
| 16 | Mississippi | 50.7 | $10,052,857 | $289,744 |
| 17 | Georgia | 50.8 | $1,223,836 | $676,856 |
| 18 | Rhode Island | 16.1 | $2,865,186 | $754,623 |
| 19 | Maine | 7.1 | $10,014,497 | $95,172 |
| 20 | Alabama | 26.6 | $331,547 | $209,399 |
| 21 | New Hampshire | 2.2 | $1,791,768 | $78,233 |
| 21 | Hawaii | 14.0 | $1,737,766 | $7,377 |
| 23 | Alaska | 1.3 | $79,250 | $19,755 |
Source: LendingTree analysis of Federal Emergency Management Agency (FEMA) National Risk Index (NRI) data. Note: Rankings were determined by a composite score in which each category was rated equally.
LendingTree home insurance expert and licensed insurance agent Rob Bhatt highlights the role of New Jersey’s expected annual building value loss in its overall ranking.
“New Jersey’s economy and population density has created demand for housing and commercial development,” he says. “These communities need to account for flood risks in land-use decisions. If we allow developers to build in areas with high flood risks, we should probably make sure they install flood control measures to help protect people and property in these areas.”
According to the U.S. Census Bureau, New Jersey had the second-highest population density of any state in 2020 (and the highest of the coastal states analyzed).
New York and Louisiana rank second and third
Following New Jersey, New York is the coastal state with the second-highest risk of coastal flooding. The Empire State has the second-highest expected annual population equivalence loss, the third-highest expected annual building value loss and the eighth-highest number of impacted square miles.
Louisiana follows. Most notably, the Pelican State has the second-largest area exposed to coastal flooding. It also has the fourth-highest expected annual building value loss and the eighth-highest expected annual population equivalence loss.
Pennsylvania and Michigan are the noncoastal states most at risk of coastal flooding
It’s not just coastal states at risk. As for the noncoastal states (with Great Lakes shorelines, plus the District of Columbia) most at risk of coastal flooding, Pennsylvania and Michigan tie for first. Most notably, Pennsylvania has the highest expected annual building value loss at $20.3 million, while Michigan has the highest number of square miles exposed to coastal flooding at 23.4.
Noncoastal states most at risk of coastal flooding
| Rank | State | Area exposed to coastal flooding risk (square miles) | Expected annual building value loss | Expected annual population equivalence loss |
|---|---|---|---|---|
| 1 | Pennsylvania | 1.7 | $20,277,586 | $1,994,021 |
| 1 | Michigan | 23.4 | $2,297,511 | $11,905 |
| 3 | Wisconsin | 4.4 | $685,055 | $2,372 |
| 4 | District of Columbia | 0.2 | $631,914 | $22,616 |
| 4 | Ohio | 3.9 | $534,036 | $2,256 |
| 6 | Illinois | 0.2 | $70,011 | $540 |
| 7 | Indiana | 0.4 | $62,399 | $159 |
Source: LendingTree analysis of FEMA NRI data. Note: Rankings were determined by a composite score in which each category was rated equally.
Following that, Wisconsin ranks third, while the District of Columbia and Ohio tie for fourth.
Florida has 758.0 square miles potentially exposed to coastal flooding
By category (and back to coastal states with ocean coastlines), Florida has the highest number of square miles exposed to coastal flooding — 758.0.
Much of Florida’s land, especially along the coast, is low-lying and near sea level, making it particularly vulnerable to flooding. Additionally, Florida has more than 8,400 miles of shoreline, according to the Florida Climate Center, which increases the area that can be impacted by coastal flooding.
Louisiana follows at a distant 429.1 square miles. Like Florida, Louisiana has low-lying topography and an extensive shoreline of 7,700-plus miles, according to the National Oceanic and Atmospheric Administration (NOAA).
Coastal states with the largest area exposed to coastal flooding risk
| Rank | State | Area exposed to coastal flooding risk (square miles) |
|---|---|---|
| 1 | Florida | 758.0 |
| 2 | Louisiana | 429.1 |
| 3 | Texas | 201.3 |
| 4 | New Jersey | 117.4 |
| 5 | South Carolina | 108.5 |
| 6 | North Carolina | 104.9 |
| 7 | Virginia | 76.2 |
| 8 | New York | 68.5 |
| 9 | California | 60.1 |
| 10 | Georgia | 50.8 |
| 11 | Mississippi | 50.7 |
| 12 | Massachusetts | 47.5 |
| 13 | Maryland | 37.6 |
| 14 | Washington | 29.9 |
| 15 | Connecticut | 27.6 |
| 16 | Alabama | 26.6 |
| 17 | Delaware | 20.7 |
| 18 | Rhode Island | 16.1 |
| 19 | Hawaii | 14.0 |
| 20 | Oregon | 8.3 |
| 21 | Maine | 7.1 |
| 22 | New Hampshire | 2.2 |
| 23 | Alaska | 1.3 |
Source: LendingTree analysis of FEMA NRI data.
Four other states have 100 or more at-risk square miles: Texas (201.3), New Jersey (117.4), South Carolina (108.5) and North Carolina (104.9).
Bhatt says it’s important to account for coastal flooding risks if you live in one of these states or plan to move to one.
“You need to have a plan to keep your family safe in the event of coastal flooding,” he says. “This includes disaster kits, go bags and evacuation plans. You also need to have a plan to protect your investment in your home. Disaster insurance (particularly flood insurance) is important because it provides the resources to pay for costly cleanup and repairs. Although flood insurance isn’t cheap, you’ll consider it a bargain if a flood damages your home.”
Expected population equivalence loss due to coastal flooding is highest in Washington
Washington has the highest expected annual population equivalence loss, at an expected $34.8 million. (Remember, this is measured in fatalities and injuries and expressed in dollars. Specifically, a fatality or 10 injuries counts as $11.6 million in economic losses.)
New York ($33.0 million) follows. Notably, New York has the fourth-highest population, at 19.6 million as of 2023, according to the U.S. Census Bureau.
Coastal states with the highest expected annual population equivalence loss from coastal flooding
| Rank | State | Expected annual population equivalence loss |
|---|---|---|
| 1 | Washington | $34,791,375 |
| 2 | New York | $33,011,662 |
| 3 | New Jersey | $28,769,710 |
| 4 | Oregon | $10,046,530 |
| 5 | Connecticut | $6,404,066 |
| 6 | Florida | $5,908,349 |
| 7 | Virginia | $3,308,596 |
| 8 | Louisiana | $2,145,380 |
| 9 | South Carolina | $1,308,813 |
| 10 | Maryland | $898,253 |
| 11 | Rhode Island | $754,623 |
| 12 | North Carolina | $699,447 |
| 13 | Georgia | $676,856 |
| 14 | Texas | $395,928 |
| 15 | Massachusetts | $351,740 |
| 16 | Delaware | $311,437 |
| 17 | Mississippi | $289,744 |
| 18 | California | $244,161 |
| 19 | Alabama | $209,399 |
| 20 | Maine | $95,172 |
| 21 | New Hampshire | $78,233 |
| 22 | Alaska | $19,755 |
| 23 | Hawaii | $7,377 |
Source: LendingTree analysis of FEMA NRI data.
New Jersey ($28.8 million) and Oregon ($10.0 million) round out the top four.
Coastal flood events have doubled or more at 21 of 33 weather sites analyzed
Among the 33 weather stations analyzed by the U.S. Environmental Protection Agency (EPA), 21 saw coastal flood events double or more from 1990-2009 to 2010-2022 — periods preset by the EPA.
Breaking that down further, Mayport, Fla., saw the biggest increase in coastal flooding events at 771.8%. That’s followed by Wilmington, N.C. (583.8%), and Charleston, S.C. (464.1%).
According to Bhatt, those events may continue to rise. “These powerful storms and flooding events are becoming more common and more destructive,” he says. “Unfortunately, these trends don’t simply reverse themselves overnight. The evidence suggests that the frequency of coastal flooding events is likely to continue to increase.”
Change in average annual coastal flood events, 1990-2009 to 2010-2022
| Rank | Station | Average number of coastal flood events per year, 1990-2009 | Average number of coastal flood events per year, 2010-2022 | Change in average annual flood events, 1990-2009 to 2010-2022 |
|---|---|---|---|---|
| 1 | Mayport, FL | 0.3 | 2.6 | 771.8% |
| 2 | Wilmington, NC | 0.5 | 3.1 | 583.8% |
| 3 | Charleston, SC | 1.1 | 5.9 | 464.1% |
| 4 | Annapolis, MD | 1.4 | 7.3 | 414.2% |
| 5 | Cedar Key, FL | 1.2 | 4.5 | 282.4% |
| 6 | Fort Pulaski, GA | 1.7 | 6.3 | 282.3% |
| 7 | Galveston Pier 21, TX | 2.5 | 9.3 | 272.3% |
| 8 | San Diego, CA | 1.5 | 5.4 | 271.4% |
| 9 | Port Isabel, TX | 0.9 | 2.8 | 234.8% |
| 10 | Baltimore, MD | 1.9 | 6.3 | 232.0% |
| 11 | Boston, MA | 4.2 | 13.0 | 213.3% |
| 12 | Washington, DC | 2.4 | 7.2 | 199.5% |
| 13 | Portland, ME | 3.4 | 9.0 | 164.7% |
| 14 | Sandy Hook, NJ | 4.2 | 10.5 | 152.1% |
| 15 | Newport, RI | 1.9 | 4.8 | 151.0% |
| 16 | Fernandina Beach, FL | 1.7 | 4.3 | 150.1% |
| 17 | Bar Harbor, ME | 4.6 | 11.1 | 139.5% |
| 18 | The Battery, NY | 4.3 | 10.0 | 132.9% |
| 19 | Pensacola, FL | 1.5 | 3.3 | 116.7% |
| 20 | Sewells Point, VA | 5.1 | 10.5 | 108.7% |
| 21 | Philadelphia, PA | 2.6 | 5.2 | 102.1% |
| 22 | Lewes, DE | 4.2 | 8.4 | 99.6% |
| 23 | Atlantic City, NJ | 5.2 | 10.1 | 93.4% |
| 24 | Los Angeles, CA | 1.1 | 2.0 | 90.5% |
| 25 | Montauk, NY | 2.3 | 4.3 | 89.1% |
| 26 | Seattle, WA | 1.8 | 3.3 | 89.0% |
| 27 | New London, CT | 2.3 | 4.0 | 77.8% |
| 28 | Kings Point, NY | 5.0 | 8.7 | 73.8% |
| 29 | St. Petersburg, FL | 1.0 | 1.7 | 69.2% |
| 30 | Friday Harbor, WA | 2.6 | 4.2 | 65.9% |
| 31 | Port San Luis, CA | 0.5 | 0.5 | 7.7% |
| 32 | La Jolla, CA | 1.9 | 1.5 | -21.0% |
| 33 | San Francisco, CA | 0.7 | 0.1 | -89.0% |
Source: LendingTree analysis of U.S. Environmental Protection Agency (EPA) coastal flooding data. Notes: The data is based on tide gauges at 33 U.S. stations where complete data is available dating to 1950. Rounded figures are displayed, but changes were calculated using unrounded figures.
On the other end of the list, only two sites saw a decrease in coastal flooding. San Francisco saw an 89.0% decrease, while La Jolla, Calif., followed at 21.0%.
Weathering the storm: Top expert flood tips for homeowners
Whether you’re moving to a coastal area or have been a homeowner in one, preparing for coastal flooding is essential. Bhatt offers the following advice:
- If you’re still in the process of buying a home in a coastal area, consider your PITI payments. “Your lender typically calculates your PITI payments,” he says. “This is an acronym for principal, interest, taxes and homeowners insurance. This is an estimate of your monthly escrow payments. If you’re moving into an area with flood risks, you should consider adding flood insurance to your PITI estimate if your lender doesn’t already do this for you because this may be a truer reflection of your monthly ownership costs.”
- Even if you don’t think you need flood insurance, consider it. “Since 20% to 25% of flood insurance claims come from outside high-risk areas, flood insurance is often worth considering if you live in a low- or moderate-risk area,” Bhatt says. “The good news is that if you’re outside a high-risk area, you’re likely to get a cheaper price on flood insurance than those in high-risk areas.”
- Look into your flood insurance options. Most flood insurance is purchased through the National Flood Insurance Program (NFIP), which FEMA manages. However, several private companies also offer it. It’s best to compare quotes for an NFIP policy to quotes from private companies serving your area.
- Weigh the pros and cons of private flood insurance. “Private flood insurance tends to offer a little more flexibility,” Bhatt says. “It’s not always cheaper, but you may be able to get more customized coverage, such as more coverage for your valuables or loss of use coverage. Loss of use covers your temporary living expenses if flood damage leaves your home uninhabitable during repairs. NFIP doesn’t offer loss of use.”
Methodology
LendingTree researchers first analyzed Federal Emergency Management Agency (FEMA) National Risk Index (NRI) coastal flooding data. Researchers utilized a composite scoring system to calculate the coastal (with ocean coastlines) and noncoastal (with Great Lakes coastlines, plus the District of Columbia) states at highest risk of coastal flooding.
The three individual categories, which were weighted equally, were:
- Impacted exposure area in square miles
- Expected annual building value loss
- Expected annual population equivalence loss
The expected annual building value loss is the average yearly loss in dollars to buildings caused by coastal flooding. FEMA used the NRI’s Value of Statistical Life (VSL) to calculate expected annual population equivalence loss. One fatality or 10 injuries equals $11.6 million in economic losses.
Researchers then analyzed U.S. Environmental Protection Agency (EPA) coastal flooding data for 33 sites along U.S. coasts. We used the average number of coastal flood events per year from 1990 to 2009 and 2010 to 2022 (periods preset by the EPA) to calculate a percentage change between the two periods.