It has been 11,000 years since glacial ice receded from New England, but many of the features of our present-day landscape resulted from the movement of the Pleistocene-era glacier.
One of the most remarkable local remnants of the glacier is a 70-mile-long ridge of gravel and sand, known as an esker, that stretches from northern Oxford County to Cumberland Center.
“The Ancestral Androscoggin Esker” is the subject of an upcoming program in the Down Home Maine lecture series, a program of the Western Mountains Senior College.
On Thursday, Sept. 8 from 5 to 7 p.m., Bob Elliott, a lifelong naturalist and environmental educator, will give a slide show and talk at Gould Academy’s McLaughlin Auditorium.
Elliott, who grew up on the Ellis River in North Rumford, is a retired University of Maine Associate Extension Professor with an MS degree in teaching, geology, and ecology.
He has been exploring the glacial features of the area for years, and previously spoke about glaciated landscapes as part of the Mahoosuc Land Trust’s 2014 “Changing Nature” series. The program on Sept. 8 will be a slightly expanded version of the 2014 program.
The Androscoggin esker was created by a river running in a tunnel through glacial ice. The river, which Elliott estimates had roughly half or more of the flow of the present-day Androscoggin, washed gravelly debris along with it.
“The tunnels are partially filled with sand and gravel, so that when the glacier finally melts, it lowers that ridge of gravel down on top of the land,” he said.
Since the early 1900s, the esker has been a source of gravel for road-building. Locally, gravel was recently mined from it for the bridge replacement project at Rumford Point.
A major aquifer located in the esker provides water for the towns through which it runs, and is also the source of the spring in Poland where Poland Spring Water is bottled.
Land features like the “Whale’s Back” in Milton and North Woodstock are actually parts of the 70-mile long esker, Elliott said.
Elliott will also give an overview of the formation of glaciers and discuss several other geological formations common in western Maine that resulted from glacial activity, including kames, kettles, potholes, and glaciated knobs.
On Saturday, Sept. 10 from 10-noon, Elliott will lead a field trip to view some of the unique glacial landscape features discussed in his presentation. Participants should meet at the south parking lot by the Gem Theater at 9:45 a.m.
Both the Down Home Maine presentation and the field trip are free and open to the public. For more information, email amy.w.chapman@gmail.com or ellenmarshall@gmail.com, or call 890-4812 or 824-2643.
Elliott will also teach a six-session course for WMSC members starting Sept. 14, which will explore in greater depth the history of glaciers, how they form and change the landscape, and the impact of climate change on glaciers.
Information on joining WMSC and registering for classes can be found at wmscollege.blogspot.com.

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