The smallest county in Texas, Rockwall County has experienced unprecedented growth in the past few years leading to an increased need for a complete update of Rockwall County’s floodplain mapping. Some maps in the county have not been updated since 1975. The Rockwall County Map Modernization will modernize the entire county with 62 miles of detailed study. All other streams in the study will be updated with new topographic information. The study began in June, 2005 and preliminary DFIRMs will be available in June, 2006.

Rockwall County covers 147 square miles and contains about 200 miles of streams. There are five communities that currently participate in the National Flood Insurance Program. The streams in the county drain into three major basins: Cedar Creek, Upper Sabine River, and the East Fork of the Trinity. Flooding in the county has been controlled by numerous SCS detention dams constructed over 25 years ago.