San Antonio Project Turns Flood Control Channel into Thriving Urban Ecosystem
By Lee Marlowe, Sustainable Landscape Ecologist
The Mission Reach Ecosystem Restoration and Recreation Project covers hundreds of acres of the San Antonio River and its riparian zone just south of downtown San Antonio. It has also led to an expansion of San Antonio’s famous River Walk, extending it by over 15 miles and connecting it to downstream historical and cultural features. The primary project goals are to maintain essential flood conveyance functions while significantly improving the ecological functions of the river and providing recreational opportunities. Key project partners include the US Army Corps of Engineers, the San Antonio River Authority, Bexar County, the City of San Antonio, and the San Antonio River Foundation.
One of the significant accomplishments of the project is that it brought life back to the river, including a diversity of native plants and animals, while also increasing opportunities for people to experience and appreciate the river and the River Walk in a new way. The project took a channelized section of the river that was little more than a drainage ditch in many people’s eyes and transformed it into a vibrant functioning ecosystem through the construction of structural habitat features and the installation of native plants, including a diversity of aquatic plants, grasses, wildflowers, shrubs, and trees. The project currently contains a habitat mosaic from open meadow areas to riparian woodlands. We expect the Mission Reach project to mature and change over time with the eventual growth of canopy tree species and forest cover in some locations and the continued growth and diversification of wildlife species.
The ecosystem restoration benefits of the Mission Reach project include improvements to the native species diversity and native plant community areal coverage, both leading to greater ecosystem stability and resiliency over the long term. The project serves as significant habitat for many species of wildlife, including resident and migratory birds, butterflies, and pollinators of all kinds. A diversity of native plants has been observed, totaling over 300 species; 170 species were installed by the project, while the rest have come in on their own. We are very close to achieving the short-term goal of 50% areal coverage by native plants within the project area and continue to strive towards a long-term goal of achieving and maintaining at least 70% areal coverage by native plants.
One of the ways we measure success is by documenting the birds that are actively using the habitat. We began the Mission Reach Avian Study in 2015 to document birds because the project serves as an essential habitat corridor and overwintering area for migratory birds; birds are good indicators of habitat variety and quality; and birds provide opportunities for education, outreach, and passive recreation. There have been over 73,000 individual birds consisting of 214 species recorded actively using the project habitat to date, with over 30 species identified as having international significance due to their annual migratory patterns covering Mexico, the continental US, and Canada.
Overall, the ecosystem restoration elements of the Mission Reach project have provided benefits for numerous wildlife species and new opportunities for visitors. Once uninviting and unappreciated by most of the public before the project, this stretch of the San Antonio River is now a destination spot and source of inspiration for visitors of all ages. People can now find many ways to enjoy the river and boost their health and wellbeing by immersing themselves in nature and participating in passive recreation such as birdwatching, exercising, learning, volunteering, and relaxing, among other activities.
For more information on the project, please visit the San Antonio River Authority website.