by Fred Bever
Maine Public news story
The beaches of southern Maine are bouncing back — ten years after a St. Patrick’s Day storm took a bite out of coastal communities and after other storms and a prolonged rise in sea levels in 2010 that caused even more erosion.
In the latest installment of “Beyond 350: Confronting Climate Change,” the future outline of these same beaches is unlikely to remain the same.
If you spend some time on the beach in Maine this summer, you might see David Cavagnaro stepping along the dune edges, wielding what looks like a long spear topped by a cylinder the size of a smoke alarm.
Cavagnaro is an intern for Maine Geological Survey marine geologist Peter Slovinsky, who uses GPS and depth-measuring systems to map the topography on and just off Western Beach in Scarborough. It’s part of an ongoing study of beach erosion — and accretion — along all of southern Maine’s coastline.
Slovinsky’s been mapping Maine’s beaches for more than a decade. In 2007 he documented the aftermath of the enormous St. Patrick’s Day storm, which caused millions of dollars in property damage. And in 2010 the beaches took a more sustained hit: That year, when sea levels in the Gulf of Maine were unusually high, a series of nor’easters marched up the coast, several right at or near high tide.
“So back in 2010 a unique set of conditions resulted in sea levels along the Maine coastline that were anywhere from 5 to 8 inches higher than normal for a period of months. So you combine the storms on top of it and you end up with very, very erosive events,” Slovinsky says.
The worst in 50 years, according to longtime area residents. And that includes Western Beach, where a seaside golf course was threatened and habitat for at-risk species such as least tern and piping plover was wiped out.
“I mean there was basically no dune, and a couple of their greens were getting eaten away. There was no habitat. There was zero habitat in 2010,” Slovinsky says.
The picture is different now. There’s a hundred feet of dry sand between the golfers and the sea. And a portion of the beach has been staked out to keep people and dogs away from nests where tern and plovers have returned in healthy numbers.
That’s in part thanks to a multimillion dollar beach nourishment project undertaken by the U.S. Army Corps of Engineers. Two years ago, sand dredged from the Scarborough River was placed on Western Beach and shaped to approximate the beach’s earlier profile.
Elsewhere on the coast, natural processes have slowly rebuilt many of the damaged beaches.
“In general, considering how erosive 2010 was due to a variety of causes, the majority of Maine’s beaches have recovered pretty well,” Slovinsky says.
Every two years, he publishes a “State of Maine’s Beaches” report, and the new edition assigns them an overall grade of “C” – satisfactory. Slovinsky adds that beaches are dynamic systems, with accretion here, erosion there — subject, sometimes, to the influence of man-made structures.
The 19th-century jetty at Camp Ellis, for instance, blocks sand from the Saco River from reaching the nearest beaches.
“Ferry Beach and Ellis Beach down in Saco, typically a lot of erosion occurs down there. And then on the converse side to that, right across the jetty here over at Pine Point and East Grand beach are some of the best performing profiles,” Slovinsky says.
And while the overall news is good, it might not last very long. Slovinsky says the Gulf of Maine’s average sea level could rise 1-6 feet or more in the next century — an effect of climate change that’s likely to be accompanied by more frequent and more intense storms.
“All of the above. It doesn’t take much for conditions to align again to have an erosive event. All it takes is one or two nor’easters in the winter season,” he says.
“There’s no question about there being a sea-level rise here, absolutely no question. But I have to deal with it,” says Graham Chase, whose home is maybe a mile from Western Beach. “I put a garden in for my parents up behind the house. And we face the marsh on the backside here, and it never flooded once when my parents were alive, and now I get ten inches water on it just about every time there’s a new moon. So this’ll probably turn into an island or disappear.”
Slovinsky says that is a possibility. Shoreline dunes can provide a good first line of defense for houses facing the open ocean, he says, and marshes can dissipate flood waters to some degree.
But low-lying roads, houses such as Chase’s and other structures — there’s a wastewater treatment plant nearby — will continue to be threatened.