STOCKTON SPRINGS, Maine – According to the Department of Conservation a coastal landslide threatening two unoccupied camps, and possibly a third, took place Thursday night along the shore at Fort Cove Point, according to Maine Geological Survey officials.
About 200 feet along the shore on Schooner Drive slid down into the water, MGS marine geologist Stephen Dickson said Friday afternoon. The top of the bluff appears to have receded about 30 feet, Dickson said.
A nearby railroad track southwest of the area also comes close to the bluff edge and could be threatened by a similar landslide, he said.
Other coastal areas in Maine, particularly those that historically experience landslides, could be in danger of landslides this weekend, Dickson warned.
“Recent heavy rains through the month of June have contributed to high water tables and saturated muddy coastal bluffs,” Dickson said. Other natural slope failures, both inland and along the banks of rivers and streams, could occur – most likely in areas where the mud thickness is 20 feet or more and saturated by a high water table, he said.
A Maine Department of Environmental Protection environmental specialist first reported the landslide Friday morning. The Maine Emergency Management Agency and the Knox County Emergency Management Agency have been notified. One of the homeowners has a private engineering consultant on site.
Dickson said he is going to the scene along with Dr. Alice Kelley of the University of Maine, Department of Earth Sciences to document the event. Kelley “has considerable experience with this subject and has mapped many MGS Coastal Bluffs Maps that are critical in identifying landslide hazard areas,” Dickson said.
The marine geologist said that while landslides are common in high clay bluffs along the Maine coast, it is not usually possible to identify a triggering event. There have been no earthquake events in recent days in New England that would have contributed to this slope failure, he said.
MGS hydrogeologist Thomas K. Weddle will be monitoring a historically unstable site in Brunswick this weekend, Dickson said.
Additional rain fall in coming days could lead to further slope instability and land loss, the marine geologist warned.
“It’s not over yet,” he said.
Conditions could worsen for the camp buildings, with the landslide continuing to eat away at more land in front of the camps, Dickson said.
He said he also was concerned about many areas up and down the whole coast of Maine that have similar high coastal bluffs, specifically those that have 20 feet or more above the high tide mark.
“These are susceptible to landslides, and we may see more slope failures in coming days,” he warned. MGS has produced “Coastal Landslide Hazards Maps” identifying areas of the coast at highest risk.
Dickson advised homeowners to look for the following features:
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signs of cracks in the lawn,
slumping on the face of bluffs,
open bare ground,and tilting trees or signs of tree movement.
In addition to rainfall, gusty winds also can threaten to destabilize slopes and move trees, he said.
Homeowners who are concerned should check with private engineering firms or qualified geologists for a site inspection.
They also can visit the Maine Geological Survey website to learn more about coastal bluffs and landslide hazards between Kittery and Schoodic Point or to add landslides to the MGS Landslide Inventory.
For more information, go to: http://www.maine.gov/doc/nrimc/mgs/explore/hazards/landslide/index.htm
What coastal landslide hazards are according to the Maine Geological Survey
Sea level is gradually rising along the coast of Maine. This rise in the ocean allows waves to erode beaches and flats at the base of coastal bluffs. Over time, erosion removes material from the base of a coastal bluff and steepens the face of the bluff. Sediments at the base of the bluff stabilize it, and when they are removed, the bluff is no longer in equilibrium. Only the strength of the material within the bluff holds the bluff in place. Continued erosion or lubrication of the bluff materials by ground water may overcome this internal resistance, particularly in clay bluffs, and result in a landslide.
Jeanne Curran
Public Information,
Maine Department of Conservation
(207) 287-3156
http://www.maine.gov/doc
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