North Carolina’s Sea Level Is Rising

The sea level off North Carolina’s coast is up to 11 inches higher than it was in 1950.¹ This increase is mostly due to ice melt, and it’s causing major issues. Solutions aren’t simple due to the state’s low elevation, extensive barrier islands, and vulnerability to coastal storms. In addition to the many people that live and work in the coastal region, and vacationers that visit throughout the year, North Carolina has vast natural resources and habitats at risk, including the largest estuarine system on the U.S. Atlantic Coast.² There are already nearly 60,000 properties at risk from frequent tidal flooding in North Carolina.³ The state is planning over $2 billion in sea level rise solutions, which include beach renourishment and improvements to reduce flooding on highways.

Sea level rise is speeding up

The sea level around Wilmington, North Carolina, has risen by 11 inches since 1950. Its speed of rise has accelerated over the last ten years and it’s now rising by over 1 inch every 2 years.¹ Scientists know this because the sea level is measured every 6 minutes using equipment like satellites, floating buoys off the coast, and tidal gauges to accurately measure the local sea level as it accelerates and changes.⁴

While there are four main causes of sea level rise in North Carolina, melting ice from the North and the South Poles and the slowing of the Gulf Stream are the two largest contributors. Because the rate of ice melt has been increasing significantly since 1992,⁵ and the fresh water melting into the ocean has been slowing down the Gulf Stream,⁶ North Carolina is particularly vulnerable to an increased rate of sea level rise in the future. Click here to learn more about these causes.

Most flooding happens during the fall

King tides are unusually high tides that are created during months when the sun, moon, and earth align. The combined gravitational pull of the moon and the sun creates much higher tides, called king tides. In some places, king tides are brought on by changes in the weather and ocean patterns. In places like Wilmington, king tides are typically over a foot higher than normal.¹ Add that to the 11 inches of sea level rise since 1950 and you end up with flooding even on sunny days.

Solutions aren’t simple

The coastline of North Carolina differs from other states with larger, urban or metropolitan areas, so solutions to sea level rise need to take into account the natural landscape and wildlife. Solutions in North Carolina aren’t simple, due to the state’s low elevation, extensive barrier islands, and vulnerability to coastal storms.

When the ocean rises high enough, high tides cause flooding even on sunny days. Even though the sea level has only risen by 5 and a half inches inches, tidal flooding has increased by 100% in some areas of North Carolina since 2000.⁹

Flooding even when there’s no rain

Drainage systems are designed to channel excess rainwater from the streets and drain it into the sea. But with the pressure from rising sea levels and higher tides, seawater can get pushed into these pipes and spill out into the streets. This causes flooding even on days without rain.

Increased storm surge flooding

Unfortunately, slightly higher sea levels make hurricanes even more damaging. Just a few more inches of sea level rise allow a hurricane to push more water onto the land, even if the hurricane itself doesn’t make landfall.

There’s a lot at risk from sea level rise and flooding in North Carolina. In addition to the many people that live and work in the coastal region of the state, and vacationers that visit throughout the year, North Carolina has vast natural resources and habitats at risk. The state possesses the largest estuarine system on the U.S. Atlantic Coast,² with an extensive barrier island chain, and over 2,300 square miles of coastal land vulnerable to a one-meter rise in sea level.²

In Hatteras there are 295 residential properties already at risk from repeated tidal flooding, by 2033 that number will increase to 434 as sea levels rise. In North Topsail Beach, 356 properties at risk will turn into 684 within 15 years. In Ocracoke there are 458 properties at risk, which will become 719. And in Surf City, there are 1,283 properties at risk, which will increase to 1,923 by 2033. Click here to explore other coastal communities in North Carolina that are at risk at FloodiQ.com.

What can you do?

Individuals, mayors, legislators, governors, and Congress can work together to build protections before flooding, to build back stronger after flooding, and to create plans that future-proof our communities. Click here to see what solutions can help protect your home or what your community can do.