CHARLOTTE, N.C. -- With flooding a real threat later this week, thousands of homes and businesses in Mecklenburg County are in the floodplain and Charlotte-Mecklenburg Storm Water Services is adding 250 more new locations to the county's flood map.

The agency sent letters to homeowners this week, alerting them of the change.

"The letters are kind of a final reminder," program manager Tim Trautman said.

"We've had many public meetings over the last four to five years, three to four public meetings and sent other letters and information to try to inform folks, but we know there's a lot going on in people's lives and it's difficult to always pay attention to it and certainly there are new property owners over the last several years that have bought property in and around the mapped areas."

The change is the result of five years' worth of work, specifically updating the floodplain in the northeast section of Mecklenburg County using new data and new technology.

Trautman said 1,700 letters went out Friday to alert about 250 people they're now in the floodplain, 250 others that they're now out of the floodplain and the rest somewhere in between.

Trautman said in all, about 4,000 homes and businesses countywide are at a one percent risk of flooding every year. Those are places experts believe will flood if 7.2 inches of rain falls within a 24-hour period.

"If more rain than that falls or it falls more intensely in that 24-hour period, we definitely can see flooding beyond the mapped floodplain," he said.

For those who now find themselves in the floodplain, there is grant money available to help minimize flooding, but of course, that grant money is not going to those people later this week.

People who fund their home with a loan are required to buy flood insurance, but the county is urging others who are close to floodplains to consider flood insurance too.

See if your home is in a floodplain in the Charlotte-Mecklenburg area.

Check out flood zones across North Carolina.

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