Some Rockford residents may have to spend thousands of dollars more to insure they're homes.
It's because they'll have to get flood insurance now that new flood maps have been drawn in town.
Technology has allowed the city to better identify where high flood risk areas truly lie.
These changes have identified over 600 homes in the city at risk in one west side neighborhood alone.
When in comes to flooding, mother nature doesn't discriminate.
But according to FEMA, there are area's with a much greater risk compared to others.
According to Illinois Water Survey Project Engineer, Amanda Flegel, any areas in Rockford, up until now were, were not, however, specified as being high risk.
"There's been a lot of development, development can increase the runoff of rain fall which goes to the streams and goes down stream and increases the flood plain," Flegel said.
Changes in landscape combined with better technology is what is causing the maps to change.
The last maps date back to the 1970's.
For people like, Illinois surveyor, Beth Grobe, better data could mean savings for her clients money.
"Now we're looking at errors this high about a tenth of an inch verses a half of a foot to a foot and a half of error," Grobe.
That little bit of error, she says can be costly, especially for residents who may not need to be on the flood map, but are.
"I've had one person who went from $780 in flood insurance to $7600 dollars in one day," Grobe said.
The reason being many mortgage companies force property owners to have flood insurance, if maps, show their property at risk.
Officials hope, aerial photography, a new technology used to help create these maps, will eliminate errors in identifying flood risk.
"We are getting more accurate, but there is still work that needs to be done," Grobe said.
Now the city will host a meeting in January to get further comment on these changes.
The maps are only a draft.
They won't be finalized until the public has given enough feedback.