The Federal Emergency Management Agency has finalized new flood insurance rate maps for portions of Montgomery County and is encouraging property owners with property along the county's floodplains to purchase flood insurance, officials said.

Flooding is the most common natural disaster in the U.S., and a separate flood insurance policy is often the most effective way to cover unexpected damages from flooding, according to FEMA.

The maps were finalized in February following an appeals process for preliminary maps issued in 2008, Assistant County Engineer Dan Wilds said. The maps will go into effect Aug. 18.

"What FEMA did to revise the maps is they attained better topographic information for the county," Wilds said. "They flew the county and used [light detection and ranging] technology to determine the ground elevation, and they basically matched the flood plains to the actual ground elevations."

The Woodlands area residents will experience some changes under the finalized maps, said Stephanie Moffett of FEMA Region 6 External Affairs.

"The main changes in The Woodlands area are along Spring Creek," Moffett said. "The San Jacinto River and other streams were redrawn using the same flood information but better topographic data."

Because flood insurance is not included in standard homeowner insurance policies, congress created the National Flood Insurance Program to provide property owners financial protection in 1968. estimates the average flood insurance policy costs about $650 per year.

The Woodlands insurance agent Rodney Fleck said some homeowners with their property now found in a flood zone may see rising insurance premiums.

"For example, a client that called in for insurance of a home, for his particular house the insurance would cost between $11,000 and $15,000 per year," Fleck said.

Fleck said it remains to be seen how the Homeowner Flood Insurance Affordability Act of 2014, which President Barack Obama signed into law in March, will affect flood insurance rates going forward.

The act reduces the recent rate increases on some policies, prevents some future rate increases, and implements a surcharge on all policyholders. The act also repeals certain rate increases that have already gone into effect and provides refunds to those policyholders, according to FEMA.

The law was enacted to repeal certain provisions of the Biggert-Waters Flood Insurance Reform Act to limit premium increases, according to FEMA.

The changes could also affect homeowners trying to sell a property that is now in a designated flood zone, Fleck said.

"If someone wanted to sell their home in a flood zone area, they would be confronted at this point in time with significant increases in their flood insurance that a buyer would be very much concerned [about] because of the cost," Fleck said.

Residents can input their address to an interactive Montgomery County flood map on the county website at to see how the new maps will affect them, officials said.