<meta http-equiv="refresh" content="0; url=https://r.sealevelrise.org/https://sealevelrise.org/risks/"/> Sea Level Rise Risks - Sea Level Rise


There’s a Lot at Risk from Sea Level Rise

It Impacts Health, Transportation, Safety, and More

There’s a lot at risk from sea level rise and flooding. Higher sea levels cause more frequent tidal flooding and worsen storm surge, which not only damages personal property, but threatens human health, emergency response time, city infrastructure, the economy, military readiness, and important habitats.

When the ocean rises, tides become higher, water can travel further inland, and even normal high tides can turn into floods. It’s like a bathtub filled close to the top: a small increase like a king tide (extreme high tide) can push the water over the edge and into the streets. As the sea level continues to rise, the bathtub becomes even fuller, causing higher flooding more often.

6.5 inches of sea level rise cause flooding with high tides


How Can Sea Level Rise Affect Communities?

It’s easy to see how flooding can inundate properties or damage cars, but sea level rise also poses a great risk to communities as a whole. Flooded roads can make it impossible to get to hospitals and nursing homes, and for police, fire, and EMS to reach their destinations, preventing response in emergencies.


Medical Facilities (Charleston, SC)

The three major medical facilities in Charleston South Carolina, (Medical University of South Carolina, Roper St. Francis, and Ralph H. Johnson VA Medical Center) experience regular flooding approximately 50 days per year. When this happens, hospitals are inaccessible, putting patients at risk and stranding workers.1

Flooding can affect businesses and the economy of a community because floods can damage shop interiors and merchandise or even force businesses to close entirely. Even if businesses stay open through flooding, they can lose sales due to customers being unable to reach shops. Tourism and port industries can be impacted or shut down by sea level rise because ports can become damaged and vacation destinations too flooded to receive visitors. In city parks, saltwater can intrude into the ground beneath trees and plants, causing them to die off. If flooding covers roads that provide access to schools, it can interrupt education.

Tourism (New Jersey)

New Jersey’s beaches account for 70% of the state’s tourism revenue, and support 10% of all jobs in the state. Sea level rise erodes natural resources like dunes and barrier islands, increasing the risk of flooding and threatening the state’s $36.4 billion tourism industry.2


How Does Sea Level Rise Change Coastlines and Ecosystems?

Rising sea levels and flooding can erode beaches and submerge coastal wetlands. Sea level rise advances the speed of beach erosion, pulling more sand from the beach into sea. Replacing the sand is possible, but expensive.3 Sea level rise is causing some islands to disappear, such as Isle de Jean Charles, in Louisiana, which will have its entire population relocated inland through a government project.4 Other states fight to preserve their last island communities, like Smith Island, in Maryland.

Beach Renourishment (Virginia BEach, VA)

In Virginia Beach, the Army Corps of Engineers replaced 1,250,000 cubic yards of sand for close to $12 million.5

Endangered species could lose their habitats to sea level rise

Rising sea levels can disrupt coastal wetlands by drowning plant species, increasing salt levels in the soil and water,6 and outpacing wetland’s migration further inland.7 This puts important ecosystems in danger, threatens habitats, and leaves communities exposed to dangerous storm surge. Without wetlands, many species could lose their homes or become extinct. Inland communities that depend on the protection from barrier islands could see worsening threat from hurricanes and storm surge flooding.

Wetlands (Atlantic Coast)

The Atlantic Coast lost roughly 20 square miles of wetlands and dry land between 1996 and 2011, all of which are now open water.8


How Does Sea Level Rise Endanger Public Health?

It can be hard to imagine the toxic and messy problems that can often be a result of flooding until it occurs. Flooding can have a significant impact on public health, as it can contaminate air and drinking water, and endanger wastewater and nuclear sites.

Sewage systems channel wastewater under the streets and to treatment plants. But rising sea levels and higher tides can cause more underground pressure on sewage systems. If these systems are damaged, it can be a costly and smelly health hazard, as well as a problem for the environment.

Sewer Systems (Miami-Dade County, FL)

In Miami-Dade County, Florida, there are already 1,000 properties with septic systems at risk or failing to the effects of sea level rise. It’s estimated that within the next 30 years, 64% of properties in the county will be compromised.9

Sea level rise can pollute air and endanger drinking water

Major flood events, including hurricane storm surge, can create moisture problems in homes and pollute air quality. Mildew and mold develop within 48 hours of exposure from flooding and can pose serious health hazards.10 Inhalation of airborne mold spores can cause respiratory problems, as well as eye and throat irritation and damage to the nervous system. The removal of mold can be done by individuals, but if too severe, will require professional removal.

As the ocean rises higher, salty water can mix with drinking water, ruining water wells and community water supplies. As water reaches further inland, communities will need to protect or move their water supplies.

Drinking Water (Broward County, FL)

In Broward County, Florida, much of the water supply for 31 different municipalities is near or in areas that already experience underground saltwater intrusion.11

Sea level rise threatens hazardous waste sites and nuclear power

Groundwater intrusion caused by sea level rise can be a serious hazard for waste containment sites and landfills. Tidal and surface flooding, elevated groundwater levels, and shore erosion can cause the release of hazardous substances.12 This could have significant consequences for communities and public health. Superfund sites, which are sites for contaminated waste or hazardous materials, are a significant risk to human health and the environment because they have the potential to leak toxic substances into soil, drinking water, and habitats.13

Many nuclear power plant facilities are located near the coast. When reactors shut down in preparation for or in response to flooding, residents that depend on nuclear power stations for their electricity can experience long-lasting power outages. As sea levels rise, more frequent and intense flooding increases the risk of off-site power losses and can impede personnel’s ability to respond to a crisis.14 Power failure can disable a reactor’s cooling mechanisms, leading to overheating and the potential for a radioactive meltdown, putting nearby coastal residents in severe danger.

Nuclear (U.S.)

Nine U.S. nuclear power plants are located within 2 miles of the ocean and four have been identified as vulnerable to storm surges and sea level rise. Since the 1980s, more than 20 flood incidents have been recorded at U.S. nuclear plants.15


Why Is Sea Level Rise Dangerous for Public Transportation?

Flooding can swamp low-lying roads, making commutes difficult or impossible and cutting off access to important city infrastructure. When flood waters inundate underground tunnels, it can leave train routes impossible to operate. Stronger storm surge brought on by high sea levels has the ability to not only shut down cities, but cause billions of dollars worth of damage and strand millions of people.

Airports, ports, and railways can be shut down

As sea levels rise, it puts airports, ports, and rail lines at risk. At least 13 airports in the U.S. have runways that are within several feet of current sea level, which means that just a few more inches of sea level rise could put them under water.16 Damage to ports from catastrophic flooding could not only shut down supply lines to certain states, but have a serious impact on the entire country. Flooding from sea level rise could shut down transit for coastal rail lines and cause major damage that could take millions of dollars to repair.

Public Transit (New York, NY)
Public Transit (New York, NY)

New York City’s public transportation is used by nearly 10 million people who rely on it daily.17 When Superstorm Sandy hit New York in 2012, it inundated railroad and subway lines and stations, vehicular tunnels, and signal equipment, causing an estimated $4.6 billion in damage.18

Railways (Connecticut)
Railways (Connecticut)

Coastal railways, such as Amtrak’s combined 115 miles of rail lines in Connecticut, are at risk. The transit lines, which span from Rhode Island to New York, not only transport over 40 million passengers but are also vital for freight transport.19

Safety & Security

How Can Sea Level Rise Impede Military Readiness and Communication?

Sea level rise poses a threat to safety and national security, as flooding can impact military readiness and shut down internet infrastructure. Rising seas erode the beaches of important military infrastructure and damage ports. Flooding can make it impossible for service-people to reach or leave army bases, and when military ports are damaged, it can not only shut down operation, but cost millions of dollars to repair.

ARMY (Norfolk, VA)

The main access road of Naval Station Norfolk floods around 10 times per year, affecting more than 90% of the servicemen, who live off base.20


Communication infrastructure could face catastrophic damage

Sea level rise can cause tides to surround traffic hubs with water, and can cause flooding in areas where important internet infrastructure is buried, cutting off internet access. Because of their locations, New York, Seattle, and Miami have the greatest risk of experiencing internet disruptions.21 The added risks of hurricanes and other extreme weather events could be catastrophic for infrastructure already at risk.

The Internet (U.S)

Estimates show that due to the effects of sea level rise, 4,000 miles of the U.S.’s buried fiber optic channels will be underwater within the next 15 years.6