The Delaware Natural Resources and Environmental Control Division of Watershed Stewardship and the Federal Emergency Management Agency will hold an open house from 4 to 7 p.m. May 23 about new preliminary flood insurance rate maps for parts of New Castle County.

The open house will be held at the William Penn High School, 713 E. Basin Road, New Castle.

The public is encouraged to attend to learn more about proposed flood risk map changes and to understand better how proposed map changes affect their property.

A partnership between the Division of Watershed Stewardship and FEMA aims to improve the accuracy of flood risk maps statewide. New preliminary flood risk maps for portions of New Castle County were released in December 2016. To get data for the preliminary flood risk maps, DNREC did hydrologic studies that determine water flows during flood events, base flood elevations and more accurate floodplain boundaries using newer elevation contours on about 150 miles of streams in New Castle County. The results enabled FEMA’s maps to show base flood elevations for many areas for the first time, providing property owners with more detailed and accurate flood risk assessments.

FEMA’s flood risk maps are used by insurance companies to establish insurance rates and by local communities to enforce local floodplain codes. Communities have recently amended local codes to adopt higher floodplain development standards, in conjunction with the release of the new flood risk maps.

Preliminary flood risk maps and current maps can be viewed at

For information on flood risk maps, call 739-9921. For information on DNREC’s flood mitigation program, visit