Flooding

Flooding is one of Maine's most frequent and damaging natural hazards. Whether from overflowing rivers, coastal storms, heavy rainfall, or ice jams, floods can happen anywhere in our state - often with little warning.

On this page:

Know Your Flood Risk

The first step to protecting yourself and your property is understanding whether you're in a flood-prone area. Use these free tools to look up flood risk for any address in Maine:

Key Facts About Flooding

  • Flooding is Maine's most costly natural hazard.
  • Homeowners insurance does NOT cover flood damage.
  • Nearly 1 in 3 flood insurance claims come from outside high-risk zones.
  • New flood insurance policies take 30 days to go into effect.
  • "Turn Around, Don't Drown" - most flood deaths occur in vehicles.

What To Do: Before, During, and After a Flood

Before a Flood

  • Know your risk. Use the tools above to check if your home or workplace is in a flood zone.
  • Get flood insurance. Standard homeowners policies don't cover flood damage. Contact an insurance agent about an NFIP policy. Remember: policies take 30 days to become effective.
  • Make an emergency plan. Know your evacuation routes. Identify where you'll go and how you'll communicate with family. Include plans for pets and livestock.
  • Prepare an emergency kit. Include water, non-perishable food, medications, flashlights, batteries, important documents, and cash.
  • Protect your property. Keep gutters and drains clear. Know how to shut off utilities. Move valuables to higher floors.
  • Stay informed. Sign up for emergency alerts. Monitor the National Weather Service and local news during storm season.

During a Flood

  • Evacuate if told to do so. Don't wait. Follow instructions from local emergency officials.
  • Never drive through flooded roads. "Turn Around, Don't Drown." Six inches of moving water can knock you down; two feet can float a vehicle.
  • Move to higher ground. If trapped in a building, go to the highest level, but not a closed attic where you could be trapped.
  • Stay away from floodwater. It can be contaminated with sewage, chemicals, and debris. It may hide downed power lines.
  • Stay off bridges over fast-moving water.

After a Flood

  • Return home only when authorities say it's safe.
  • Document damage. Take photos and videos before cleaning up. This helps with insurance claims.
  • Avoid electrical hazards. Don't touch electrical equipment if wet or standing in water.
  • Clean and disinfect. Everything touched by floodwater may be contaminated. Wear protective gear.
  • Watch for mold. Mold can develop within 24-48 hours. Dry out your home quickly.
  • Seek help. Contact your insurance company. Check if FEMA disaster assistance is available.

Do I Need Flood Insurance?

Standard homeowners, renters, and business insurance policies do not cover flood damage. Only a separate flood insurance policy covers the cost of repairing or rebuilding after a flood.

You may be required to have flood insurance if:

  • Your property is in a high-risk flood zone (Zone A or V on FEMA maps)
  • You have a federally-backed mortgage (FHA, VA, USDA, or conventional from a federally-regulated lender)

Even if not required, flood insurance is worth considering. Nearly one-third of claims come from outside high-risk zones.

How to get flood insurance: Contact any licensed insurance agent to purchase an NFIP policy. Visit FloodSmart.gov for more information.

Types of Flooding in Maine

Maine experiences several types of flooding. Understanding these can help you recognize risks and respond appropriately.

Riverine (River) Flooding

River flooding occurs when water levels rise above riverbanks due to heavy rainfall, snowmelt, or both. Maine's major river basins are all susceptible to spring flooding when warm temperatures rapidly melt accumulated snowpack.

Ice Jam Flooding

Ice jams are a significant flood hazard in Maine. They form when warming temperatures and rain break up river ice, and chunks pile up at bends, bridges, or narrow channels. The ice acts like a dam, causing water to rise rapidly upstream. When ice jams suddenly release, they can send a torrent of water and debris downstream. Ice jam floods are particularly dangerous because they can occur with little warning.

Flash Flooding

Flash floods occur when heavy rain falls in a short period, overwhelming streams, drainage systems, and low-lying areas. They are especially dangerous because they develop quickly, sometimes within minutes. Flash floods can happen anywhere it rains, including areas not typically considered flood-prone.

Coastal Flooding

Maine's 3,500 miles of coastline are vulnerable to flooding from storm surge, high astronomical tides, and waves driven by powerful storms. Nor'easters and hurricanes can push ocean water inland, particularly when storms coincide with high tide (called "storm tide"). Sea level rise is gradually increasing the baseline water level, making coastal flooding more frequent. The Maine Climate Council recommends planning for 1.5 feet of sea level rise by 2050 and 4 feet by 2100.

Lake (Lacustrine) Flooding

Lake flooding occurs when a lake's outlet cannot discharge water fast enough to maintain normal levels. During major flood events, some Maine lakes can rise 1 to 5 feet above normal, with some extreme cases exceeding 15 feet. Properties built close to the water's edge, particularly older camps, may be vulnerable.

Urban/Surface Water Flooding

In developed areas, flooding can occur when drainage systems are overwhelmed by heavy rain. Impervious surfaces like roads, parking lots, and rooftops prevent water from soaking into the ground, increasing runoff. This type of flooding is typically shallow but can cause significant damage to basements.

Dam Failure

While rare, dam failures can cause rapid and devastating downstream flooding. Maine has hundreds of dams of varying age and condition. Communities downstream of dams should be aware of emergency action plans. For more information, visit Maine's Dam Safety Program page

Notable Floods in Maine's History

Maine has a long history of significant floods, the study of which can help us prepare for future events.

The Great Flood of 1936

Region: Central and Southern Maine

Two back-to-back rain events on ripe snowpack caused catastrophic flooding throughout the Kennebec, Androscoggin, and Saco River basins. Ice floes destroyed bridges. The flood destroyed or damaged 81 highway bridges, caused five deaths, and resulted in $25 million in damage (1936 dollars). This flood established the peak of record at numerous streamgages—a benchmark that stood for over 50 years until 1987.

February 1976: "Groundhog Day Storm"

Region: Bangor and Penobscot Bay

Downtown Bangor flooded with 12 feet of water - the first documented tidal flood at Bangor. Storm surge combined with high astronomical tide pushed water up the Penobscot River. Flood waters rose in less than 15 minutes, trapping office workers and submerging ~200 vehicles.

April 1987: "April Fool's Day Flood"

Region: Central Maine

Record peaks occurred at 13 of 35 USGS streamgages. The flood exceeded the 1936 benchmark throughout the Kennebec, Androscoggin, and Piscataquis River basins. Damages affected 14 of 16 counties, with 2,100+ homes flooded, 215 destroyed, and 240 with major damage.

October 1996: Southern Maine Flooding

Region: York and Cumberland Counties

Up to 19 inches of rain fell over two days, shattering Portland's 24-hour rainfall record by more than 5 inches. The Presumpscot River peak was 68% higher than any flow in the previous 102 years. This event showed extreme flooding can occur outside spring snowmelt season.

April 2007: "Patriots Day Flood"

Region: Southern and Central Maine

Up to 8.5 inches of rain fell on 6-12 inch snowpack, causing rapid runoff and snowmelt. Storm surge and four high-tide cycles caused tremendous coastal and river damage. Peak streamflows exceeded 100-year recurrence intervals in York County. Two lives were lost when people attempted to cross flooded roads.

April-May 2008: St. John and Aroostook River Flooding

Region: Aroostook and Penobscot Counties

Record snowfall during the 2007-2008 winter, combined with 1.5 to 5 inches of rain, caused record flooding on the St. John, Fish, and Aroostook Rivers. Over 600 people were evacuated and multiple streamgages recorded all-time record levels.

December 2023 / January 2024

Region: Central Maine and Coastal Communities

The Androscoggin River at Rumford crested at the 3rd highest level on record. The Kennebec at Augusta reached near 3rd all-time. The NWS classified it as central Maine's most severe flood since 1987. Back-to-back coastal storms in January caused historic storm surge along Maine's working waterfronts, prompting emergency declarations.

Additional Resources

Flood Preparedness and Safety

Flood Insurance

Flood Maps and Risk Data

Current Conditions

Climate and Sea Level Rise