The Hydrologic Engineering Center of the U.S. Army Corps of Engineers developed the River Analysis System, HEC-RAS, to replace the HEC-2 hydraulic model. The memorandum titled "New Policy for the Use of HEC-RAS in the NFIP" addresses the policy for the use of HEC-RAS to replace HEC-2 models for flood hazard mapping efforts for the National Flood Insurance Program (NFIP).
The memorandum titled "HEC-RAS Version Update" addresses the decision making process that FEMA contractors and mapping partners should apply to flood map revision requests involving HEC-RAS.
To view or download the Policy for the Use of HEC-RAS in the National flood Insurance Program (Apr 2001), click here.
To view or download the HEC-RAS Version Update, click here.