SCARBOROUGH — Peter Slovinsky, a marine biologist with the Maine Geological Survey, sees a lot of high water in the future of Scarborough’s coastal and shoreline areas.

“Count on a foot increase (in sea level) by 2050 and a 2-foot increase by 21oo,” Slovinsky said in a workshop Wednesday about proposed changes to town floodplain management ordinances.

Don Hamill, who owns property on Pine Point and off Broadturn Road, said those forecasts do not mean town councilors should be in a rush to approve sweeping changes affecting construction of existing and new structures in areas deemed flood zones by the Federal Emergency Management Agency.

The changes requiring new construction, rebuilding of damaged properties or renovations costing more than half the current worth of a structure to be set 3 feet above the floodplain instead of the current 1 foot, have been discussed by town planners, Planning Board members and councilors since the summer.

The proposed changes, which will be discussed Oct. 29 at a Planning Board public hearing and could face a second vote by councilors Nov. 7, came as a surprise to about 20 residents attending the workshop led by Slovinsky and Assistant Town Planner Jay Chace.

Chace and Slovinsky represent the town as part of the Sea Level Adaptation Working Group, a combined effort in Saco, Old Orchard Beach, Biddeford and Scarborough to proactively confront effects of rising sea levels. Officials in the towns are working with the Southern Maine Regional Planning Commission on strategies and solutions and funding options for implementation.

The “SLAWG” acronym is awkward, Chace admitted, but similar zoning requirements were enacted in Saco earlier this year and have the potential to for big savings on flood insurance premiums for property owners in FEMA flood zones.

By increasing the base structure height to 3 feet above a floodline, shifting heating and electrical systems above ground, and using posts or flow-through foundations to prevent inundations by storm surges, Chace said a study by Gorham-based Chalmers Insurance Group shows homeowners could save 67 percent on flood insurance premiums that are required with mortgaged properties in flood zones.

Based on current FEMA maps, Chace said about 1,000 properties are affected by the revisions, and 267 of them are currently insured against floods.

The ripple that became the swell ridden by Hamill and Pine Point residents John Thurlow and Judy Shirk is new FEMA maps expected to be released next spring or summer. Slovinsky said the maps update 30-year-old data and use enhanced technology to determine wave and water flow.

Updated floodplain maps were released for Cumberland and Yrok counties by FEMA in 2009, then withdrawn when the mapping methods were questioned by town officials and residents.

Hamill said the Planning Board and town councilors should wait for new FEMA maps to get a better idea how many properties will be affected in the future. As the workshop concluded, Thurlow urged his neighbors and other residents living in shoreline neighborhoods to attend the hearing and subsequent council meeting to ask for a postponement of the zoning revisions.

Slovinsky and Chace emphasized that the floodplain maps and SLAWG efforts are not mutually inclusive. Based on readings taken in Portland harbor over the last century, sea levels are rising, they said.

“I really don’t care why it is rising,” Slovinsky said, “Sea-level communities like Scarborough are the ones feeling it now.”

The prediction of a 2-foot rise in sea levels in the next 80 years are based on studies including data on melting ice sheets, and Slovinsky said the increase will be most notable in summer months when offshore winds push currents to beaches.

The real hazards come when storms arrive, especially if a storm surge coincides with a high tide.

Slovinsky said flood tides combined with a 2-foot increase in sea levels could produce flooding like the Patriot’s Day Storm in 2007 “on a monthly basis.”

The zoning ordinance revisions are the first efforts by SLAWG members to legislate action against rising sea levels, but Chace said other municipal department heads also have the data and reports.

Additional actions could include redesigning or relocating public infrastructure in vulnerable area and elevating roads, but Chace said his department is concerned only with zoning.

David Harry can be reached at 781-3661 ext. 110 or dharry@theforecaster.net. Follow him on Twitter: @DavidHarry8.