The Science of Flood Management

Managing Our Flood Risk

Proper watershed management is the first step to lessening disastrous flooding.

Exactly what is a watershed?

It is all the land area that drains water into a common place, usually a river, stream or lake.  Weather events happening miles and miles away from these bodies of water can dramatically affect their levels, flow and intensity and cause severe flooding.   

Implementing appropriate management practices is important to sustaining and enriching life in the San Antonio River Watershed and control the devastating effects of flooding. The goal of the River Authority is to reach a sensible balance between physical, chemical, biological and economic factors while still maintaining the integrity of the watersheds throughout the San Antonio River Basin.

Because these factors are always evolving, an effective watershed management plan involves a never-ending cycle of planning, assessing, and implementing.

Here’s a closeup look at a Watershed Management Cycle:

Aerial view of flood waters held back by levee
Watershed Management Cycle

Collect water at specific locations and test to gather specific data.

Compare current water quality to state and federal standard or establish desired future conditions.

Develop goals and strategies to maintain or achieve water quality standards and meet future demands.

Implement goals and strategies through public policy, best management practives (BMPs) and education.

Determine the specific watershed and issues to be studied. Identity the stakeholders and resource personnel.

The River Authority constantly measures results to make sure the watershed management plan is performing at its highest level and adjust the program where needed.

Data Driven. Scientist Approved.

Another invaluable tool for flood control is a Watershed Master Plan.

It helps educate everyone about changes in land use, potential new building projects and modifications to regulations governing development within the basin. It’s particularly important as an information tool for decision makers whose actions and policies can affect the health of a watershed.

As the regional technical planning lead in watershed management, the San Antonio River Authority has made significant investments in collecting and maintaining watershed data and developing complex analytical tools and models to make scientifically sound watershed management recommendations.

City planners working with flood map

What's in Your Watershed?

The Watershed Master Plan Viewer displays information from the various Watershed Master Plan reports, as well as other useful reference data. This tool assists the stakeholders, decision-makers, and the public visualize and understand the challenges and potential solutions to watershed management. Explore your watershed using our Watershed Master Plan Viewer:

Alerts

Mission Reach Area Maintenance

Update (December 2025): Crews will be moving south of Concepcion Park towards the baseball fields around the Mission Road area. The trail in this section will be closed the morning of Wednesday 12/10 and is expected to reopen the later next week.  Work will also continue at the current location near mile marker 8.2 for the remainder of the week, where crews will be cleaning the area and hauling off chips and debris. This section of the trail will remain open When: Beginning October 20, 2025 through Spring 2026 What: Crews will be performing stem-density removal and related vegetation maintenance along sections of the Mission Reach to help manage flood risk and protect surrounding infrastructure. Some trails or segments may be closed temporarily while work is underway. Why: Removing excess stems that naturally establish along the river helps maintain stormwater conveyance, reduces flood risk, and protects public infrastructure while allowing grassland and native vegetation to recover and thrive. What to expect:
  • Limited trail closures and intermittent work zones.
  • Crews and equipment working near the riverbanks during daytime hours.
  • Parking areas remain open, but visitors may see signage and temporary barriers.
Questions? Call the San Antonio River Authority at (210) 227-1373 or visit https://www.sariverauthority.org/services/river-health/ecosystems/. Thank you for your patience while we keep the Mission Reach safe, clean, and enjoyable. Stem Density work 12.10.2025-12.19.2025

Trail Closure – Mission Reach Area

The Acequia Park trailhead entrance at Probandt Street to the Bexar County Public Works Department building's trailhead will be closed through December 23rd due to construction. We apologize for the inconvenience.

Trail Closure Alert – Calder Alley, San Pedro Creek

Maintenance work will be done in Calder Alley starting Wednesday, September 18, 2025.
  • Trails will remain open during this work.
  • One bench at a time will be temporarily barricaded while improvements are completed.
  • There may be occasional contractor pickups in the area.
We appreciate your patience as we continue to maintain and improve San Pedro Creek for all to enjoy!

SASPAMCO Paddling Trail

The SASPAMCO paddling trail is open from River Crossing Park to Helton Nature Park. *Please Note: Paddling Trail from Helton Nature Park to HWY 97 is still closed due to blockages. 

SASPAMCO Paddling Trail Temporarily Closed

Staff have removed two large log jams just downstream of Helton Nature Park, keeping the southern portion of the SASPAMCO Paddling Trail temporarily closed. Staff are working to contact adjacent landowners to support a land-based removal solution.

Goliad Paddling Trail Alert

NOTICE: HWY 59 Landing Site Closed Due to TxDOT construction on the HWY 59 Bridge, the HWY 59 landing site is closed until further notice. However, the Goliad Paddling Trail remains open, and paddlers can still access the river at the Riverdale, Ferry Street, and Goliad State Park landings. Please plan accordingly and check back for updates.

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