Two intense storms in the last year and the likelihood of more prompted the City Council recently to budget $140,000 for shoring up two stretches of public shoreline.

On the east side of Armistice Bridge, a large block of granite — one in a row of stones that doubled as benches — tumbled down the bank after an October 2017 storm.

City Planner Wayne Marshall reported this among a half-dozen instances of rapid erosion on city land caused by storms in recent years.

Speaking to the city's Climate Change Committee Nov. 14, Marshall said the stones at Armistice Bridge, also known the footbridge, were placed four feet from the edge of the slope when they were installed three years ago.

"There is something really significant that happened in the last two years," he said.

The October 2017 storm, and another in March of this year, cut deeply into the bluff along the shore at City Park.

Will Gartley of Gartley & Dorsky, a Camden-based engineering and surveying firm hired by the city to consult about the erosion, said he visited the park several times during moderate storms as saw waves coming three-quarters of the way up the bank. The water at the shore was brown from soil that was being swept away, he said.

The two sites haven't been formally surveyed, but Gartley gave an informal opinion to members of the Climate Change Committee and city staff members that the slopes would probably need to be armored with rip rap.

Done properly, Gartley said, the treatment, which uses large stones, would last at least 25 years.

"The only failures have been when people are reluctant to use large-enough stones," he said.

Committee secretary Barbara Bell said 25 years isn't long in the context of ongoing climate change. She and other committee members asked about a potentially more resilient treatment known as "living shorelines" that uses salt-resistant plants to stabilize the bank, or alternatively "managed retreat" in places where trying to stop erosion would amount to fighting an expensive, and ultimately losing, battle with nature.

Gartley said vegetation alone wouldn't be enough in the two city locations, because the slope rises steeply from the high tide line, but he supported a combination of stones and vegetation. Managed retreat, he said, would mean giving up land that never can be reclaimed because federal and state regulations protect everything below the high tide line.

Paul Beal, vice chairman of the committee, suggested appealing to regulators because the rules are based on an assumption that the tide line remains the same from year to year.

"The whole issue of climate change says it ain't necessarily so," he said.

Gartley said regulators haven't been willing to consider allowing property owners to reclaim land from natural bodies of water, even when it can be proven that the shore has eroded significantly in a short time.

Gartley & Dorsky estimated in September that erosion control would cost $71,050 at City Park and $68,775 at Armistice Bridge. The council approved spending up to $140,000 from the city's capital projects account in the 2018-19 budget.

The city has identified other locations in need of erosion control, including Robbins Road, Thompson's Wharf and the city landing.