Some Ellis County residents in the coming weeks will get notified that the floodplain classification for their property may be changing.

The change is being made based on new maps developed with digital technology for determining elevation, according to Mason Ruder, environmental planning supervisor for Ellis County.

“FEMA and the Kansas Department of Agriculture Division of Water Resources started a project a few years ago on updating our paper maps that are currently from 1986 for the floodplain,” said Ruder, speaking Monday evening to the Ellis County Commissioners during their regular meeting at the Ellis County Administrative Center, 718 Main St.

Using three-dimensional elevation information captured with LiDAR, or light detection and ranging technology, FEMA and state officials have developed new maps considered more precise than the current ones, Ruder said.

“Currently, they’re at the point in the process they’re getting ready to open public comments for the map,” he said. “So they’re compiling a list of the potentially impacted properties, and once they have that list they’re going to send it to us, and I’m working with the cities of Hays, Ellis and Victoria to work on a plan to send the notifications out to these people.”

The maps are considered a draft at this point so property owners can submit their comments about the changes, either online or at a November open house in Hays.

“There will be an open house Wednesday, Nov. 6 at Sternberg,” Ruder said. “There will be engineers on hand. KDA will have staff. FEMA will have staff there as well, to go over what it means if their property will be floodplain now, how it will affect their flood insurance, and allow them to make comments on the draft map.”

The Nov. 6 meeting is from 2-7 p.m.

“Hopefully, we’ll get the list this week,” Ruder said. “This is not a final map; this is just the draft. It will be sometime in 2021 when the map is potentially adopted.”

It’s without a doubt that some properties will change classification.

“In some areas, the map will expand the floodplain area,” he said. “And in others, it will change in a way that benefits property owners.”

LiDAR gathers elevation by flying a plane over the ground and using light to measure the distance from the ground up, Ruder explained. From those measurements, technicians built a draft map, and the process now is to ensure there are no abnormalities.

“Is what you’re sending out, Mason, the homeowner’s new flood classification?” asked County Commissioner Dustin Roths.

“They’ll get a notification saying ‘Hey, there could be a major change coming your way,’” Ruder said.

Property affected may have a zone A, or high-risk, flood zone running through it, he said. So someone with a federally backed mortgage, for example, may have to buy flood insurance through FEMA now, or someone planning a structure with a new floodplain running through it may have to change their plans, apply for a map amendment or take steps to build out of the floodplain.