A highway floods in San Antonio in 1998.

Draft Floodplain Maps & Public Meetings

As the Authority on flood safety and a cooperating technical partner for the Federal Emergency Management Agency (FEMA) the San Antonio River Authority (River Authority) invites you to come view the Bexar County draft floodplain maps. Attendees will have the opportunity to look up any property of interest within the County on the draft map alongside a River Authority engineer. In addition, staff from the City staff and other government agencies will be available to answer questions on flood insurance, floodplain regulations, and upcoming or potential projects relating to flooding/drainage in the area. The River Authority is taking initiative in sharing the draft floodplain maps with the community ahead of FEMA’s formal map adoption process.

On-site Spanish Speakers will be available

View Draft Floodplain map 

Frequently Asked Questions

Draft Floodplain Map Public Meeting Locations & Dates

All Public Meetings have concluded. Please view the Draft Floodplain Maps in the link above or Contact Us with further questions. 

How to Submit an Appeal

When the Preliminary Flood Insurance Rate Maps and Flood Insurance Study Report are published, there will be a 90-day appeal period. During this period, any owner or lessee of real property may file an appeal with their municipality's floodplain administrator. 

Find your local floodplain administrator at TexasFlood.org

Read More about the Appeals Process PDF Download 

Frequently Asked Questions

The San Antonio River Authority (River Authority) has interlocal agreements with Bexar County, City of San Antonio, and 19 suburban cities within Bexar County to maintain the floodplain maps for their jurisdictions. The River Authority is also a Cooperating Technical Partner with the Federal Emergency Management Agency (FEMA). Through this partnership, FEMA recognizes the River Authority’s floodplain mapping role, performed on behalf of the local communities.

Day-to-day, the floodplain maps are maintained through Letters of Map Revision. Letters of Map Revision are small-scale floodplain map updates and usually cover small areas like lots or individual neighborhoods. These revisions typically reflect changes to the floodplain that result from construction activity. Less frequently, widespread updates covering an entire county are needed to keep the floodplain mapping data current.

There is new rainfall, land use, and topography data that affects all of Bexar County. The last study of the floodplains in Bexar County used terrain and land use data from around 2004 and rainfall estimates based on data from the 1960’s. This was the best available data at that time. Since that time enough information and data is available to warrant an update of the floodplain maps. Updated information includes the National Oceanic and Atmospheric Administration’s (NOAA) estimates of how much rain will fall in large storms, the Texas Natural Resources Information System’s (TNRIS) ground surface elevation data, and the River Authority’s land use data. These inputs for the new floodplain mapping study were developed and collected from 2017 to 2019. The engineering studies to develop the draft floodplains have been underway since 2019.

We estimate the new floodplain maps will become effective in 18-24 months. The River Authority provides draft floodplains to FEMA, and FEMA continues the process of formalizing the floodplain map panels. FEMA will issue Preliminary Flood Insurance Rate Maps (FIRMS) and then provide the public a 90-day appeals and comment period. Effective FIRMS will be published after responses are reviewed and incorporated. The River Authority is starting the public engagement process early to provide the community with ample time to review and provide comments on the maps.

The engineering data is being made available immediately on the River Authority’s Digital Data and Modeling Repository (D2MR) website for use as “Best Available Data.” D2MR website is a well-known and used tool within the development engineering community.

Bexar County and all the cities in Bexar County have special regulations for activities inside the floodplain intended to reduce flood risk to life and property. Residents and business owners will need to coordinate with their jurisdiction’s floodplain administrator to obtain a permit for construction or building improvements.

If a property owner has a federally backed mortgage on a property in the floodplain, they will be required to purchase flood insurance. Based on data from the National Flood Insurance Program from August 31, 2022, the average annual cost for flood insurance premium and associated fees in Bexar County is $783.45. The average coverage including building and contents is $285,505. For more information about flood insurance, property owners can speak with their home insurance provider, keeping in mind that flood insurance is separate from home insurance.