Marion and Mattapoisett homeowners have less than a month to appeal changes to floodplain maps and potentially save money on insurance premiums.

Representatives from the Federal Emergency Management Agency and National Flood Insurance Program met with residents Thursday night in an effort to clear up any confusion regarding the new maps—which will be finalized at the beginning of 2012—and how they affect homeowners’ insurance policies and premiums.

Floodplain designation would also bring restrictions to which new construction would have to conform.

The towns can vote to adopt or reject the maps at the spring Town Meeting. If adopted, they would go into effect either June or July 2012. Rejection would bring potential penalties in the form of ineligibility for some federal programs.

The maps are available in the Town Halls.

The most notable change is a 2-4-foot increase in elevation in the description of what qualifies as floodplain -- thus putting land into flood zones that, because of its slightly higher elevation, was previously just outside the flood zone.

Residents who have been placed in a higher-risk zone for the first time have the opportunity to “grandfather,” or lock in, the current zone designation on their insurance policy. This can be done in two ways: Purchase a policy before the appeal deadline (Dec. 2) or provide evidence that the structure was built in compliance with initial map rates.

Grandfathering a policy does not, however, lock in current rates, according to FEMA official Lauren Pawlik.

Pawlik also said getting flood insurance was important even for those not in flood zones.

Richard Zingarelli, State Coordinator for the National Flood Insurance Program, stressed the importance of reviewing the maps.

“When banks review their mortgages, which they will, they’ll hire a company to look at what zones structures are in,” he said. “And they won’t look that close. That is why you need to look at these maps and file an appeal.”

Appeals can be made by filing a Letter of Map Amendment, which requests a special flood hazard zone designation for structures or land be removed.

Pawlik said an executive summary of construction standards and insurance rates for each town will be made available soon.

Click here to view Letter of Amendment forms.