An effort by the state to save a Popham Beach bathhouse with a temporary seawall of fallen trees and beach scraping is an example of an appropriate engineering endeavor to save beach-front property without harming the landscape, according to research by a University of Maine professor.
Joseph Kelley, professor of marine geology in the University of Maine’s Department of Earth Sciences and cooperating professor at the Climate Change Institute, studied a 2009 action by the Maine Division of Parks and Public Lands to save public property from beach erosion by mimicking natural processes.
“This paper points out that in special circumstances, engineering efforts, which typically destroy the dynamic of beaches and dunes, can prove beneficial,” Kelley says. “We hope these approaches work, but erosion on other parts of the beach is continuing.”
Previous approaches used to slow beach and property erosion in Maine are no longer allowed or economically feasible.
In Maine, seawalls were banned in 1983. Replacement of storm-damaged buildings is also not allowed, and a precedent case on Popham Beach in the 1980s ruled an owner had to remove an unpermitted building from a site where an earlier structure was damaged, the study states.
So when erosion threatened the newly built bathhouse on the parking lot at Popham Beach in 2009, the the remaining options for the state were moving the building back from the ocean — a costly choice — or applying temporary measures.
Because the inlet channel causing the erosion would eventually change course, the state decided to create a temporary seawall with fallen trees at the site. In December 2009, the Maine Bureau of Parks and Lands roped together fallen pine trees and secured them to standing trees on the top of the dune. The treewall was legal as a temporary structure and lessened wave and current energy in an attempt to reduce erosion. The creation of the treewall was also used to assure the public that action was being taken, according to the study.
Once the inlet channel changed course, beach scraping was used. Sand was scraped from the lower to the upper beach — without adding new material — to deflect the current away from the bathhouse.
The use of temporary solutions of beach scraping and biological barriers successfully saved the building without having to create a permanent structure or resort to expensive replenishment, Kelley writes.
“Popham Beach, Maine: An example of engineering activity that saved beach property without harming the beach” was published in the peer-reviewed science journal Geomorphology.
Contact: Elyse Kahl, 207.581.3747