Giving Mother Nature a Helping Hand
 he recharge initiatives project involves forcing additional stream flows into the Edwards Aquifer. This is done by building recharge structures either on or above the recharge zone. SAWS is reviewing two types of recharge structures for possible use. These are:
- Type I structures built above the contributing zone to hold back storm runoff and then release it slowly across the recharge zone, allowing more water to seep into the aquifer.
- Type II structures built directly over the recharge zone to impound storm runoff, allowing it to recharge directly into the aquifer. Type II structures have been identified as SAWS’ choice for further analysis.
SAWS is involved in several studies that may result in potential projects relating to recharge structures. The Cibolo Watershed and Nueces River Basin studies are being conducted by the U.S. Army Corps of Engineers (Corps), and an additional study conducted in cooperation with the Edwards Aquifer Authority (EAA) is assessing Recharge and Recirculation.
Cibolo Watershed Study
The first study SAWS engaged in with the Corps was the Cibolo Watershed Study, a watershed approach to ecosystem restoration and flood damage reduction. The potential recharge structure contained in this study is included as ecosystem restoration. Recharge to the Edwards Aquifer is considered as ecosystem restoration because of the beneficial impact to Comal Springs. However, depending on the final location of the proposed recharge/flood reduction structures, the Trinity Aquifer also could benefit with increased recharge. In either scenario, SAWS would benefit.
Cibolo Study Sponsors – Corps, San Antonio River Authority, Guadalupe-Blanco River Authority, SAWS
Timeline – Three-phased study, from 2002 through 2008; currently in Phase III
Nueces River Basin Study
The Nueces River Basin Study is the largest and most comprehensive study in cooperation with the Corps. The scope of this multipurpose feasibility study represents a holistic approach to address Nueces River Basin ecosystem restoration, flood control, aquifer recharge, water supply, water quality, brush management, and overall watershed resource management. Collectively, these components are expected to function as a system and designed to accomplish the following goals:
- Restore ecosystems of the Nueces River Delta through increased freshwater inflows.
- Increase volume and reliability of spring/base stream flows via aquifer recharge enhancements for the benefit of endangered species and water supply for communities dependent on the Edwards Aquifer.
- Reduce damage associated with flooding events in the basin.
There are four potential recharge structure sites identified in this study, all located in the Edwards Recharge Zone.
Nueces Study Sponsors – Corps, Nueces River Authority, City of Corpus Christi, San Antonio River Authority, Guadalupe-Blanco River Authority, SAWS
Timeline – Three-phased study, from 2004 through 2010; currently in Phase II
Recharge and Recirculation Study
SAWS is continuing the Recharge and Recirculation Study (R&R), originally initiated by the EAA. Phases III and IV include the following: evaluation of potential operational parameters, water sources and costs for various R&R scenarios. The primary goal of R&R is to increase the overall storage of water in the Edwards in order to increase firm water supply and ensure spring flow.
R&R Study Sponsors – Edwards Aquifer Authority and SAWS
Timeline – Expected completion date of December 2007 |
