The Federal Emergency Management Agency has finalized a set of flood maps for portions of southeast Bexar County that will become effective in July.

The newly approved FEMA maps cover sections of China Grove, Elmendorf, San Antonio, St. Hedwig and unincorporated areas of Bexar County. Over the next six months, FEMA officials will work with these cities and the San Antonio River Authority to update floodplain ordinances in these areas accordingly.

The river authority also recently launched the process of updating the flood maps for incorporated areas of Bexar County and the City of San Antonio. Those are expected to be finalized within the next 18-24 months.

To help residents understand the draft maps, the river authority is hosting 10 open houses across Bexar County through the end of March so people can learn if their home or business could be affected — and what they should do about it, if anything.

The river authority hosted its first open house earlier this month, to show off the first new floodplain maps in 13 years.

The newly-approved FEMA maps cover an area known as the Calaveras watershed, which is based around Calaveras Lake and Creek, said Erin Cavazos, a senior engineer with the river authority.

“We can help residents with questions about these maps as well,” Cavazos said.

As a “cooperating technical partner” of FEMA, the river authority is the official maintainer of Bexar County’s flood maps. The process to update the maps for the maps for the unincorporated areas of Bexar County began roughly four years ago; FEMA announced the maps are now finalized earlier this month.

The new maps can help residents understand their property’s flood risk — although FEMA and local officials emphasize that flooding can happen anywhere; the maps simply show where a community is most at risk of flooding.

Insurance companies and lenders use flood maps to determine flood insurance requirements and policy costs.

By understanding flood risks, property owners can decide which insurance option is best for their situation. Community leaders can use the maps to make informed decisions about building standards and development that will make the community more resilient and lessen the impacts of a flooding event.

Flood insurance is available through private policies or the National Flood Insurance Program (NFIP). Residents with federally backed mortgages must have flood insurance if their structures are in Special Flood Hazard Areas.

A FEMA map specialist can also help residents answer questions about the new maps by calling 877-FEMA MAP (877-336-2627) or emailing

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Lindsey Carnett

Lindsey Carnett covers the environment, science and utilities for the San Antonio Report.