Phase 1 of the Comal County Map Modernization project was initiated in October 2003, and entailed GIS-based hydrologic, hydraulic modeling updates, and re-mapping of the rivers and streams in that county. This project is one of the first studies under the FEMA Map Modernization Program that will produce completely digital flood insurance study products for the nation. Digital Flood Insurance Rate Maps (DFIRMs) will replace the current FIRMs and will include database information related to underlying base maps and technical data.

Phase 2 began in August 2004 and the hydrologic, hydraulic and mapping effort was completed in June 2006. The official appeals period started on September 13, 2007 and ended on December 11, 2007. Maps will be finalized after all appeals are resolved.