A flood is a temporary submerging of typically dry land as a result of the overflow of inland or tidal waters as well as the rapid accumulation of the runoff of surface waters from any source. Due to the state’s geography, floods in Maine are usually fast rising but last for a short amount of time. The most common types of floods in Maine include:
- Flash Floods/Urban Flooding: Quickly rising small streams after heavy rains, ice jams or rapid snow melt. Urban flooding refers to the overflow of storm sewer systems due to poor drainage at the time of flooding.
- Riverine/Ice Jams: Periodic overbank flow of rivers and streams.
With 5 major rivers, more than 5,000 streams and brooks, 6,000 ponds and lakes and 3,500 miles of coastline, water abundance is one of the State’s most valuable natural resources as well as its primary hazard. Because of Maine’s geography, many of its rivers flow steeply from the mountains eastward toward the sea. Rivers in mountainous regions tend to rise very quickly after heavy rainfall. Generous precipitation (about 42.6 inches a year) contributes to flood potential as well.
In Maine, floods can happen during any season, but are most common in the spring due to the combination of steady rainfall and snowmelt. Summer flooding is caused by intense rainfall from thunderstorms while flooding during the fall is typically the result of intense rainfall after light to moderate rainfall has saturated the ground. Floods are uncommon during the winter because most precipitation occurs in the form of snow.
Severe flooding can cause loss of life, property, damage, disruption of communications, transportation, and electric service and community services, crop and livestock damage, health issues from contaminated water supplies, molds and mildew within structures, and loss and interruption of business. Firefighting efforts can potentially be compromised.
You can find out more about flooding in Maine from the U.S. Geological Survey.
Notable Floods in Maine
March/April 1987: Due to the combination of normal snowpack and normal flood potential, a warm rainstorm brought 4-6 inches of rain to the state already covered in about 6 inches of melted snow. The water ran over frozen ground, causing streams and rivers to rise. Flood damage in the Penobscot and Kennebec River basins in 1987 was the greatest for any flood in Maine. At least 2100 homes were flooded, 215 were destroyed and 240 suffered major damage. Roads and bridges were destroyed and at least 400 small businesses were impacted, causing over $100 million in estimated damages.
The Flood of 1936: In March 1936, the combination of heavy rains and melting snow contributed to the flooding [throughout New England](http://www.erh.noaa.gov/nerfc/historical/mar1936.htm ). Many areas dealt with the worst flooding they had ever experienced. The Kennebec, Penobscot, Androscoggin and Saco River Basins all suffered flooding, washing out roads and some bridges in the surrounding areas.
Mitigation
The damaging effects of flooding can be lessened when development in flood ways is restricted and when existing structures are flood-proofed. Flood warnings can enable residents and businesses to evacuate and/or institute whatever procedures are necessary to protect themselves and their property. Adequate emergency plans for communities, businesses and individuals located in vulnerable areas can also minimize impact.