2017-07-13 / News

Community comes together to chart beach erosion

By Grant McPherson
Staff Writer


From left, Caley Mackenzie and Aaron Snyder of the Ecology School in Saco demonstrate how to measure erosion for the volunteer beach profile monitoring program. Mackenzie said once a month she will measure four locations along the beach in Camp Ellis. She said measuring the beach in June is much more enjoyable than during the winter months. (Grant McPherson photo) From left, Caley Mackenzie and Aaron Snyder of the Ecology School in Saco demonstrate how to measure erosion for the volunteer beach profile monitoring program. Mackenzie said once a month she will measure four locations along the beach in Camp Ellis. She said measuring the beach in June is much more enjoyable than during the winter months. (Grant McPherson photo) SACO – Sandy beaches in southern Maine are under a greater threat than ever from coastal erosion due largely in part to human impact. Researchers at the Maine Geological Survey and the National Weather Service in Gray have been studying erosion patterns in York County with help from the Maine Sea Grant program at the University of Maine. Volunteers in Saco and Old Orchard Beach have been providing information to the Maine Sea Grant to help better understand the health of their beaches and how communities can better respond to the issues facing them.

Volunteer coordinator for the beach profile monitoring program Jacob Aman said volunteer data has been collected over the past 20 years on beaches in southern Maine. He said the group has had success getting communities involved with coastal resource management and research.

“We’ve been able to better understand changes that take place seasonally and over time,” Aman said.

Aman said beach profile monitoring volunteers take measurements once a month throughout the year. Volunteers use two one and a half long meter sticks attached by a three meter long rope to measure from the dunes down to the water line and take 60 to 100 measurements from the same locations every month using reference points on land such as electrical poles or houses. The data is then graphed to show increases or decreases in dune height along the beach.

Aman said sandy beaches in Maine in general are losing sand and as sea levels rise, waves and storms deposit sand further up the beach. Aman said in locations where there is a sea wall or development directly adjacent to the sand dune the beach has nowhere to move. Adding sand to the beach, for example from a river dredge, he said, adds to the short-term supply but doesn’t seem to last long term.

“After five years the sand doesn’t stay on the beach,” Aman said.

Aman said the rate of sea level rise is increasing in Maine and by 2100 could rise anywhere between 1 and 6 feet. Beaches could naturally migrate inward toward land, something that poses a threat to places with roads and houses. Aman said after Hurricane Sandy in 2012 a federal program was put in place to buy out coastal property owners in New Jersey. Aman said he doesn’t know of any similar plans in Maine.

Aman said the jetty in Saco Harbor is directly responsible for the erosion at Camp Ellis. Any proposed solution there, he said, would be expensive.

“It’s a question of political will and money,” Aman said. “There have been fixes suggested for the Saco jetty but funding is limited.”

Caley Mackenzie, residential program manager at the Ecology School in Saco, said she’s been profiling the beach in Camp Ellis for the past three years. She said part of her job is teaching students about the impact humans have on the environment. Mackenzie said construction of the jetty began in the 1800s to help boats reach factories further up the Saco River.

“As soon as the last part of the jetty was completed, the mills on the river started to close,” she said.

There has been discussion about removing the jetty, but, Mackenzie said it would cost a lot of money and most scientists think it would take 100 years for the natural sand cycle to return to the way it was prior to the jetty’s installation.

“There are lots of pros and cons all the way around,” Mackenzie said.

Mackenzie said the Ecology School has been profiling Camp Ellis beach for at least the past 16 years. Monitoring erosion is their way of caring for the environment around them. She said organizing beach profiling can be difficult, especially in winter. An average profiling session, Mackenzie said, takes about forty minutes. A few weeks ago Mackenzie noticed the crest of a dune had moved.

“You can see the difference almost month to month, the way the sand and dunes change,” Mackenzie said.

Peter Slovinsky, a geologist with the Maine Geological Survey in Augusta, said erosion is natural after severe storms. He said as sand is pulled away from a beach it is placed on nearby shores and sand bars. Those sand bars then disrupt larger waves and push the sand ashore again. Slovinsky said erosion naturally occurs over the course of the winter, when there are typically larger waves and more frequent storms, but dunes begin to recover starting in the spring and summer as gentler waves pack sand on the beach.

“Beaches respond almost as a living creature,” Slovinsky said.

Slovinsky said beaches have moved toward land in response to long-term sea level rise. The Maine Geological Survey works closely with property owners and municipalities to understand how best to respond. Slovinsky said in response to the 2007 Patriot’s Day storm, the city of Saco mandated homes be built three feet above base flood elevation in certain shoreline areas.

Slovinsky said he along with other geologists hope to release the State of Maine’s Beaches Report 2017 on Friday, July 14. According to the Maine Sea Grant website, the biennial report discusses the signifi- cance of volunteer data collected, seasonal and long-term trends and the health of beaches across the state. Slovinsky said this year’s report will hopefully coincide with the Beaches Conference at Wells High school scheduled for July 14. Slovinsky said beach profile monitoring volunteers are given free attendance in return for their service.

John Cannon, senior meteorologist for the National Weather Service, said volunteer data helps in his forecasting of beach erosion and coastal flooding. He said he also has volunteers measure erosion right before and after a significant nor’easter. Cannon said this is important because beaches often replenish themselves within the normal monthly timeline.

“We want to study snapshots of how single storms affect erosion along the coastline before the beach is replenished,” he said.

Cannon said some storms can add sand to the dune. He said longer and more gradual waves can bring sand onto the beach and deposit it there. Cannon said how much sand is added depends on the storm strength and type, among many factors.

“We’re beginning to understand how wave battering is an important factor in beach morphology, especially for vulnerable beaches,” he said.

Cannon said because dune monitoring is difficult in the winter, there are few examples of dune surveys before and after storms. He said the darkness and large waves prevent volunteers from taking accurate measurements. Cannon said the volunteer data has been crucial in con- structing their latest models.

“We can use research to help forecast waves and their impact on the shoreline,” Cannon said. “It’s a great example of a collaborative effort.”

Aman said the program is always looking for more volunteers and anyone interested can contact him directly at jacobaman@wellsnerr.org or visit http://www.seagrant. umaine.edu/extension for more information. Contact Staff Writer Grant McPherson at news@inthecourier.com

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