The intersection of East Basse and Jones Maltsberger Road routinely floods during heavy rains in San Antonio. Photo by Iris Dimmick.
The intersection of East Basse and Jones Maltsberger Road routinely floods during heavy rains in San Antonio. Credit: Iris Dimmick / San Antonio Report

Sponsored by

The San Antonio River Authority (SARA) is rolling out a web-based tool as part of Risk, Mapping, Planning, and Assessment (Risk MAP), a Federal Emergency Management Agency (FEMA) program currently being implemented across the country. SARA recently completed the first batch of flood risk data for the Upper San Antonio River Watershed and the Salado Creek Watershed. The results from those studies are available at

In 2003, SARA signed an agreement with FEMA to serve as a Cooperating Technical Partner (CTP). As part of the broader National Flood Insurance Program (NFIP), FEMA collaborates with designated CTPs to develop and maintain current flood-hazard maps, information, and tools.  In its CTP role, SARA is tasked with implementing Risk MAP on FEMA’s behalf within its four-county jurisdiction, and in the portion of the San Antonio River Basin that reaches outside its jurisdiction.  Through FEMA’s Risk MAP program, SARA has conducted watershed-based studies to improve engineering credibility, producing a more comprehensive perspective to understanding flood risks. While Risk MAP flood risk products are non-regulatory and do not directly modify flood insurance rates as determined by existing Flood Insurance Rate Maps (FIRMs), they provide invaluable tools for planning and mitigating flood risk.

For several years, SARA has been working with floodplain administrators throughout the basin to identify study needs. Once needs have been identified, SARA applies for FEMA grants to help fund the identified studies. Ongoing and recently completed studies focus on three primary goals. The first goal is to obtain sound data, which ensures that flood risk assessments are based on the most current, reliable data available.

The second goal of the Risk MAP effort is to better communicate risk to local planners and the general public. Older mapping products come up short in providing accurate representations of actual risks, and lack risk assessments of areas that fall outside the floodplain. The SARA/ FEMA partnership seeks to remedy this by providing tools that help users visualize their own risk. The third goal is to provide a set of tools that can help communities with developing mitigation plans. Such plans may include project development, ordinance revisions, and evacuation route planning.

As SARA rolls out watershed study results, ongoing studies continue on the Medina River, Cibolo Creek and Lower San Antonio River watersheds. SARA plans to deliver on those results over the next couple of years.  Maintaining and improving these data sets continue to be at the forefront of SARA’s vision for risk assessment throughout the San Antonio River basin, as engineers focus on adding more detail to the flood risk tool.

Risk MAP is producing the most up to date flood hazard information and risk assessment tools, enabling communities to shape flood mitigation plans with more precision, resulting in greater protection of life and property. By creating accurate representations of flood risks, and providing outreach and support, SARA hopes to empower communities throughout the San Antonio River Basin to make more informed decisions about planning and reducing flood risks. To know your risk, visit

Avatar photo

San Antonio River Authority

The San Antonio River Authority was created in 1937. Its jurisdiction covers 3,658 square miles – all of Bexar, Wilson, Karnes, and Goliad counties.