Edwards Aquifer
Why is the Management of the Edwards Aquifer Such an Important Issue for the Guadalupe River?
Springs from the Edwards Aquifer are the sources of tributary rivers to the Guadalupe River. Water from the Edwards Aquifer flows from Comal Springs in New Braunfels into the Comal River. Water from the Edwards Aquifer flows from San Marcos Springs in San Marcos into the San Marcos River. The Comal and San Marcos Rivers are major tributaries to the Guadalupe River.
The average annual contribution of Comal & San Marcos Springs discharge to the Guadalupe River is 373,000 acft. The average discharge of the Guadalupe is 1.25 million acft. While the contribution of the springs during droughts decreases as surface water runoff is unavailable, it actually increases in terms of the proportion of the flow that is provided during droughts. For example, during portions of 1996 the springs accounted for 70% or more of the flow reaching Victoria and nearly 40% of what reached San Antonio Bay. There are seven endangered and one threatened species that live in Comal and San Marcos Springs. These aquatic species are protected by the federal Endangered Species Act.
Below you will find information regarding the regulation, management, hydrology, policy and natural history of the Edwards Aquifer.
Information Regarding Edwards Aquifer Management, Regulation and Policy
- The EAA's Junior-Senoir Water Rights Program and the Proposed Critical Habitat Listing for Three Endangered Aquatic Invertabrates
- Extended Chronology of Drought in the San Antonio Area
- Witte Museum 2006 Edwards Aquifer Conference Presentation (6.0MB)
- Letter To The Editor From General Manager - October 2000
- Permit Reductions Effective January 1, 2004
- SAWS letter to USFWS
- Quarles Letter to USFWS
- An Analysis Of The Take And Jeopardy Flows For The Fountain Darter Including Potential Flows Required By The Endangered Invertebrates Of Comal Springs
- The Little Fish That Roared: The Endangered Species Act, State Groundwater Law, And Private Property Rights Collide Over The Texas Edwards Aquifer
- Management Of The Edwards Aquifer; A Work In Progress
- Raiders of the Lost Aquifer? Or, the Beginning of the End to Fifty Years of Conflict over the Texas Edwards Aquifer
- Texas Parks and Wildlife Commission Briefing
- Letter from Representative Carter Casteel Addressing Concerns about the Regional Water Situation
- Neigbors Criticize SAWS Water Resources Plan
- San Antonio Greater Chamber of Commerce Questions SAWS Water Resources Plan
- Comments on SAWS Water Resources Plan from the Members of the South Central Texas Regional Water Planning Group
- Shutting Off Water Projects Bad Move for Alamo City
- GBRA Letter to USFWS Regarding Draft Habitat Conservation Plan
- Chronology of Recent Events Regarding the Edwards Aquifer
Important Documents from the Edwards Aquifer Authority
- Edwards Aquifer Authority Final Regulatory Impact Assessment For Proposed Rules Chapter 711, Subchapters E (Groundwater Withdrawal Permits), G (Groundwater Available For Permitting; Proportional Adjustment; Equal Percentage Reduction) And K (Additional Groundwater Supplies)
- Edwards Aquifer Authority Regulatory Impact Assessment For Proposed Implementation Rules
- Evaluation Of Augmentation Methodologies In Support Of In-situ Refugia At Comal And San Marcos Springs, Texas
- Evaluation of the Availability of Additional Water Supplies From the Edwards Aquifer
South Central Texas Water Advisory Committee
- Edwards Aquifer Authority response to South Central Texas Water Advisory Committee Resolution No. 02-2004-01 requesting the Edwards Aquifer Authority Board of Directors to reconsider its approval of Resolution and Order No. 12-03-478 Adopting permit rules within Chapter 711 of the Edwards Aquifer Authority rules
- South Central Texas Water Advisory Committee Resolution and Order No. 02-2004-02
- A Resolution Of The South Central Texas Water Advisory Committee Requesting The Edwards Aquifer Authority Board Of Directors To Reconsider Its Approval Of Resolution And Order No. 12-03-478 Adopting Permit Rules Within Chapter 711 Of The Edwards Aquifer Authority Rules
- A Resolution Of The South Central Texas Water Advisory Committee Requesting The Texas Commission On Environmental Quality To Review The Action Of The Edwards Aquifer Authority Board Of Directors Approving Resolution And Order No. 12-03-478 Adopting Permit Rules Within Chapter 711 Of The Edwards Aquifer Authority Rules
- South Central Texas Water Advisory Committee Resolution Requesting Review Of Edwards Aquifer Authority Board Of Directors' Action
- Joint Resolution by the South Central Texas Water Advisory Committee and the Guadalupe Basin Coalition Requesting that the SAWS Board Postpone Action on their Water Resources Plan
- TCEQ Resolution on SCTWAC's Appeal of the EAA's Junior/Senior Pumping Rights Program
The Guadalupe-Blanco River Trust was founded in 2001 to conserve land in the Guadalupe River Watershed.