IH-35 Water Supply Project
Regional Water Overview
- Many of Texas’ fastest-growing areas draw their current water supply from underground aquifers.
- The difficulty in determining the capacity of most aquifers, their susceptibility to drought-related pumping shortages, and their complex hydrologic relationship with rivers, springs and environmental issues makes ground water challenging to incorporate into long-term water and economic development planning.
- As a result, the San Antonio/Austin region is focused on locating and obtaining alternative surface water supplies that can be part of a dependable, water management and planning process.
How is Hays County Affected?
- Hays County, located along the rapidly-growing I-35 corridor, has some of the highest growth rate projections for Texas.
- Its location just south of the Austin/Travis County metroplex, and the availability of Hill Country acreage, makes it a destination of choice for suburban residential growth and the commercial and industrial services needed to support this growing population.
- Most of the county is served by groundwater wells drawn from two major aquifers. The Edwards in the south and southeast serves communities along I-35 including San Marcos, while the Trinity (and Glen Rose) in the north and northwest supply water to Dripping Springs and other nearby areas.
- Protecting these aquifers is important. Pumping from the Edwards Aquifer is limited by S.B. 1477, which placed a 450,000 acre/foot/year pumping cap on the aquifer and established the Edwards Aquifer Authority to manage this resource by protecting spring flows. A separate agency -- the Barton Springs/Edwards Aquifer Conservation District -- regulates the aquifer in northern Hays County beginning near Kyle and including the area around Buda. The BS/EACD has different pumping caps from the EAA.
- The Trinity Aquifer is smaller and has a limited water supply. This also limits growth and the ability to plan for future economic development in this portion of the county.
- The Hays-Trinity Groundwater Conservation District was authorized by the last legislative session and serves the southwestern portion of Hays County.
GBRA’s Commitment to Water Resource Protection
- GBRA has provided leadership in water-related services to residents of the Guadalupe River Basin since 1933. Our involvement in resource protection is indisputable, beginning with our landmark work in soil conservation during the 1940’s and our pioneering development of a water quality laboratory and testing procedures in the late 1960’s. We are committed to continuing this responsibility as unprecedented growth creates increased demand for limited ground and surface water supplies.
- GBRA is helping areas that rely on groundwater and aquifers to develop dependable, alternative water supplies that will support current and future growth requirements.
- GBRA has dedicated years of manpower and financial resources to protect the spring flows and endangered species at Comal and San Marcos Springs.
Hays County Regional Initiatives
City of San Marcos Water Treatment Plant
In 1994, the Texas Water Development Board funded a grant study with GBRA, the cities of San Marcos and Kyle, and nine rural water supply corporations to explore the benefit of combining resources to build a regional water treatment and delivery facility for communities and water systems in the Hays County and San Marcos area. The San Marcos Regional Water Treatment Plant (SMWTP) is the result of this study.
In 1997, the San Marcos City Council and the GBRA Board approved a contract to build a regional water treatment plant near San Marcos. In July 1998, the City of San Marcos broke ground for the initial phase of the treatment plant and selected GBRA as the contract operator. Construction was completed and water production began in 2000. The plant is owned by the City of San Marcos which contracts with GBRA to purchase 5,000 acre feet of Canyon Reservoir stored water annually. GBRA diverts this water from Lake Dunlap through a pump station and pipeline it owns and operates, and delivers the water to the plant for treatment and distribution.
San Marcos WTP Expansion
GBRA is working with the City of San Marcos on a planned expansion of the water treatment plant from 9 million gallons per day (MGD) to 21 MGD. GBRA will be constructing an expansion of the raw water pump station at Lake Dunlap and a booster pump station with two, 1 million gallon tanks off Centerpoint Road. Both these projects are scheduled to be completed by late 2007.
IH-35 Water Supply Project
GBRA has completed construction of a treated water delivery system from the San Marcos Water Treatment Plant (SMWTP) to northern Hays County. System components include a pump station at the SMWTP, a 500,000 gallon storage tank, and approximately 22 miles of 12-inch to 30-inch diameter pipeline, which runs parallel to IH-35 to the City of Buda. The estimated cost of the project was approximately $20-million and is funded by GBRA through the sale of bonds on the open market.
Contracts are in place with the City of Kyle, the City of Buda, the Sunfield Municipal Utility District and Goforth Water Supply Corporation. These customers contract with GBRA to purchase raw water from Canyon Reservoir, which is treated at the plant and delivered under a separate contract on a wholesale basis through the distribution system.
The project is capable of delivering up to 6 MGD with an ultimate capacity of 12 MGD.
| Current Customers | Initial Delivery Date | Current MGD | Ultimate MGD |
| City of Kyle | September 25, 2002 | 1.14 | 2.64 |
| City of Buda | September 19, 2006 | 0.5 | 1.0 |
| Goforth Water Supply Corporation | August 30, 2006 | 0.36 | 0.93 |
| Sunfield MUD | 0.0 | 4.0 |
In September 2006, GBRA and the Hays County Commissioners Court approved a non-binding interlocal agreement. Under the agreement, GBRA and Hays County will jointly explore the possibility of providing surface water – potentially through a pipeline from the San Marcos Regional Water Treatment Plant -- to the Village of Wimberley and other rapidly-growing portions of the county currently served by wells.
Rev. November 16, 2006
The Guadalupe-Blanco River Trust was founded in 2001 to conserve land in the Guadalupe River Watershed.