Draft and effective flood maps answer different questions in Bexar County

Two flood-map views help answer different Bexar County questions. FEMA's National Flood Hazard Layer shows the flood zones now in force. The San Antonio River Authority also posts newer studies and draft floodplains. Those drafts use newer data on rain, land use, and ground height.

A draft line is an early look at modeled risk. It is not yet a FEMA zone in force. For a federal mortgage, the map in force is used to decide if flood insurance is required. A lender or insurer may still look at other risk data. Land outside a mapped high-risk zone can still flood.

A buyer, builder, or owner who is renewing coverage should check both maps. Search the address in FEMA's Map Service Center and the River Authority viewer. If the lines differ, ask the local floodplain office which map controls your permit or other decision.