State officials presented the latest proposed flood map update to the public during an open house Monday night.

As part of the Federal Emergency Management Agency’s effort to modernize the maps, the Georgia Department of Natural Resources has headed up the state project, moving to an online accessible Digital Flood Insurance Risk Map.

“It’s been quite some time since there has been an update to the flood hazard areas in Forsyth County,” said Collis Brown, Georgia floodplain management coordinator, during the presentation.

The county sent about 2,800 letters to residents who the preliminary map shows will have new floodplain on their property, Brown said.

A couple hundred attended the open house to get more information about how the map changes could affect them, and in particular what it may mean for their insurance.

Any home in the special flood hazard area, a high-risk zone, is required under the national program to buy flood insurance, Brown said.

Those areas have been identified as a 1 percent per year risk of flooding, formerly referred to as the 100-year flood zone, he said.

The process of updating the map began in early 2009 by gathering data to update or replace the information included in the previous, and outdated, map, said Garrett Skinner, project manager of contracted engineering firm Atkins.

“Because of the limited level of accuracy with the data that was developed over five, 10 years ago that currently exists on your maps … FEMA and DNR began the process of collecting more accurate data,” Skinner said.

The final map will become effective in September 2012, when the insurance requirements will also kick in.

Residents have from November through February to appeal any scientifically or technically incorrect information on the map to DNR.