Buildings such this one at 196 Front St., in Ferry Village could be threatened by impending climate change, a recent survey found. Contributed

SOUTH PORTLAND — Historic buildings in Ferry Village may be under at least 6 feet of water by 2100, according to a recent survey conducted by Greater Portland Landmarks.

The survey, which began on June 18 and ended in mid-August, documented historic properties in the city that are at an increased risk to the impacts of climate change, according to Julie Larry, director of advocacy for Greater Portland Landmarks, who presented the information at an Aug. 29 GPL meeting.

The survey, partially funded with a grant from the National Park Services’ Historic Preservation, has been entered into the Maine Historic Preservation Commission’s database, but it’s only the first phase of a long-term effort to help cities such as South Portland protect historic homes.

A map of Ferry Village shows houses surveyed, in red, with the green overlay being the projected sea level rise by 2100. Contributed

The end goal of the project, Larry said, is to provide property owners with resources and assistance on how to mitigate the impacts of damage in the future. She also hopes it will help cities take action on mitigating the effects of climate change.

Ferry Village, the city’s oldest neighborhood, is located between the Fore River and Broadway and close to Southern Maine Community College. According to Larry, the popular residential area is 175 acres and encompasses 280 historic properties built prior to 1969.

Over the summer, four interns surveyed 458 buildings in the area and 98 garages, photographing historic buildings in the neighborhood and collecting building information to determine their risk of damage in rising sea-level events.

Waterfront areas along Front and High streets are predicted to be susceptible to rising sea levels. Less well known is the potential for flooding deep within the neighborhood along Sawyer, School and Stanford streets.

South Portland’s Ferry Village Neighborhood has been shaped by over 150 years of shipbuilding and the people who built their lives around the industry through World War II. Although shipbuilding diminished after the war, the neighborhood remains a popular residential area.

Many historic properties, Larry said, have basement windows that are quite close to the ground, a total of 62% of the buildings surveyed in the neighborhood. No distinction was made regarding which ones were potentially too close to the ground and could be entry points for flooding.

The survey also found that 18 buildings have streets that are higher than the front entrance of the property. This is important, Larry explained, because property owners don’t want water running from the street into the front door of a historic home.

Laying down seeds and mulch can also have an impact on how easily water can drain from properties. About a quarter of the buildings surveyed showed drainage running toward the property and not the street, which could cause issues in flooding events.

Shade trees also pose a threat to historic locations, with data showing almost 120 of the 400 houses surveyed have shade trees that could be brought down in bad weather or extensive flooding. Larry said while this concern doesn’t necessarily apply just to rising sea levels, it’s important to take into consideration for the longevity of historic properties.

In addition to the survey, Larry said ideas are being considered to determine how the issues will be addressed in the future, although specifics are still uncertain.

In 2020, she explained, the organization will focus on draft recommendations to protect buildings in the future that Larry hopes will be used in a joint Climate Action and Adaptation Plan formed by the cities of South Portland and Portland in March 2018.

“South Portland could take large steps to deal with the flooding in their area,” said intern Sarah Knauer, who worked on the project over the summer. “This could take the form of revamping drainage for the area or constructing appropriate sea barriers to protect this coastal area. This would allow homeowners to stay and invest in sump pumps and other household alterations to weather increasing storms, flooding, and sea rise.”