<meta http-equiv="refresh" content="0; url=https://r.sealevelrise.org/https://sealevelrise.org/states/maine/"/> Maine's Sea Level Rise - Sea Level Rise

Overview

Maine's Sea Level Has Risen 8” Since 1950

And Initial Solutions Will Cost Over $100 Million

The sea level off Maine’s coast is 8 inches higher than it was in 1950.1 This increase is mostly due to due to changes in ocean circulation2 and ice melt.3 Solutions in Maine can be complicated because the state has to find solutions that protect communities from sea level rise while also protecting and preserving important coastal habitats.4 The state currently has estimates for over $100 million in sea level rise solutions, which include beach renourishment, raising roads, and stormwater management.

Sea level rise is speeding up

Although the sea has only risen by 8 inches since 1950, its speed of rise has accelerated over the last ten years and it’s now rising by about 1 inch every 8 years.1 We know this because the sea level is measured every 6 minutes.6 Scientists use different equipment like satellites, floating buoys off the coast, and tidal gauges to accurately measure the local sea level as it accelerates and changes.

Created with Highcharts 6.2.0

Sea level measurement from Bar Harbor area tide gauge since 1950

Causes & Complications

Why Are Sea Levels Rising?

While there are four main causes of sea level rise in Maine, changes in ocean circulation2 and ice melt3 are the largest contributors. Because the rate of ice melt has been increasing significantly since 1992, and changes in ocean circulation are causing coastal storms such as Nor’easters to increase in frequency and intensity, Maine is particularly vulnerable to sea level rise.7 Click here to learn more about sea level rise causes.

Gulf Stream
How Ocean Circulation Increases Sea Level Rise
Ice Melt
How Ice Melt Increases Sea Level Rise

Most flooding happens in the winter

The highest tides in Maine occur during nor’easters, wintertime storms that push more water to the coast, raising high tides even higher. Combined with an increased gravitational pull from the moon, these tides are typically nearly two feet than normal high tides.1 Add that to the 8 inches of sea level rise since 1950 and you end up with flooding even on sunny days.

Solutions aren’t simple

Solving for sea level rise in Maine can be complicated, because the state is home to important wildlife and endangered birds as well as many coastal communities that require barriers to protect them. Solutions will need to integrate natural infrastructure into communities in order to successfully protect the coastal habitats and ecosystem that endangered species rely on, while also saving towns and cities from rising seas.

Forecast

What's the Future of Sea Level Rise?

In the last decade, the speed at which Maine’s sea level is rising has increased, and is now rising by about 1 inch every 6 years. Around Bar Harbor, it took 52 years for the sea level to rise around 6 inches.1 Scientists now forecast that in the next 16 years, the sea will rise by another 6 inches.6

Scientists are not certain how fast the ocean will warm and ice will melt. They expect water levels to continue to rise faster, but are not sure just how fast. Therefore scientists from the National Oceanic and Atmospheric Administration (NOAA) and the US Army Corps of Engineers (USACE) have made predictions based on ranges from low to high.

Below you can see the range of the NOAA and USACE high and intermediate forecasts for various locations around Maine.9 We are currently closest to the USACE high forecast, which is the darkest red line.

SLR speeding up - Maine English
SLR speeding up - Maine English
Bar Harbor
Created with Highcharts 6.2.0Bar Harbor Sea Level Rise Forecasts

Flooding

Why Are Floods More Frequent?

When the ocean rises high enough, high tides cause flooding even on sunny days. Even though the sea level has only risen by around 3 and a half inches, tidal flooding has increased by 157% in Maine since 2000.8

Flooding
How sea level rise affects Maine

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.

Drain A
Drainage Under Normal Tidal Conditions
Drainage With King Tide / Sea Level Rise

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.

ME-blizzard

Blizzard, January 2018

Higher sea levels create a higher launching point for storm surge. These small changes in sea level rise are enough to turn what were 100-year storm surges into much more frequent events. In fact, in a third of 55 coastal sites studied throughout the US, 100-year storm surges will be 10-year or more frequent events by 2050.11

This means that in many coastal cities, if you bought a house with a 30-year mortgage today, by the time you paid off your mortgage you could be experiencing extreme 100-year storm surges ten times more frequently due to sea level rise alone. This does not include the added risk of more intense storms resulting from warmer water and a warmer atmosphere, which could further increase storm surge damage.

In January of 2018, a major blizzard hit Maine, bringing tidal flooding that was the highest on record in four decades. Portland recorded the third-highest tide since weather officials started keeping track over 100 years ago.12 Without sea level rise, this blizzard’s storm surge would have been much lower.

ME-blizzard

Blizzard, January 2018

Costs

What's at Risk in Maine?

There’s a lot at risk from sea level rise and flooding in Maine. Not only is the state’s $3.5 billion tourism economy that it heavily relies on at risk, but countless dune and coastal wetland habitats are as well. These wetlands and beach ecosystems provide an important defense against coastal flooding, and are important breeding grounds for osprey, heron, several types of fish, and endangered species such as the Saltmarsh Sparrow, Roseate Tern, and Piping Plover.13 Without this natural defense system, coastal homes, highways, and wastewater management and transportation infrastructure are all greatly at risk from sea level rise and flooding.14

Business & Economy
Business & Economy

Flooding can damage sales, shop interiors, and merchandise, and force businesses to close. Tourism and port industries can be impacted or shut down by sea level rise.

Beaches
Beaches

Rising seas increase the speed of beach erosion, pulling more sand from the beach into sea. Replacing the sand is possible, but expensive.

Coastal Wetlands
Coastal Wetlands

Sea level rise can disrupt coastal wetlands, which puts important ecosystems in danger, threatens habitats, and leaves communities exposed to dangerous storm surge.

Maine will need to spend over $100 million on solutions

Some cities have sufficient resources to deal with this problem while others do not. Maine will need solutions at the individual, local, state, and federal levels to protect its coastal communities.

Saco
Saco

The US Army Corps of Engineers has proposed a $27 million project to prevent continued erosion of the Camp Ellis Beach shoreline in Saco, ME.15

Damariscotta
Damariscotta

Damariscotta has determined that flood projects to fortify the town’s coast and mitigate flooding will cost an estimated $1.7 million.16

Portland
Portland

Portland has over $100 million in estimates for mitigation projects that include raising roads and stormwater management.17

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.