Skip to Content

Mission & Vision

Edwards Aquifer Research and Data Center Building.

The Edwards Aquifer Research & Data Center (EARDC) was established in 1979 with special funding for Texas State University to provide a public service in the study, understanding and use of the very fragile natural resource, the Edwards Aquifer. The aquifer is a unique, world-renowned karst aquifer that is made up of porous, permeable limestone. It supplies water of exceptional quality to over 2.0 million people in the San Antonio area and neighboring cities. Springs from the aquifer feed the Comal and San Marcos rivers which provide base flow in the Guadalupe River system. The aquifer and its associated spring support the habitat for nine species listed as endangered or threatened by the federal government. EARDC takes an active role in water education issues and works daily with public schools as well as institutions of higher education. Annually since 1989, our center has given some 40 tours to more than 1,000 elementary and secondary school students as part of their science field trips. Seminars and workshops are held frequently to promote water education and water conservation. The center also provides laboratory analysis of 4,000 water samples a year to more than 100 customers. EARDC operations are organized around four major areas:

Expand All Content
  • Operating both statewide and nationally, collects, maintains and makes available information on the Edwards Aquifer. The information is stored in six major categories:

    1. Base Data: maps, aerial photography and related media
    2. Meteorological Resources: Data from the National Weather Service and Texas Natural Resources Information System (TNRIS) are available, including information on precipitation, evaporation, humidity, solar radiation, wind speed and direction.
    3. Biological Resources: Information about species composition, distribution and dynamics.
    4. Water Resources: The Texas Water Oriented Data Bank in Austin, accessed via our computer, provides available surface and groundwater data. Much of the data in the local area are available in our own files.
    5. Geologic and Land Resources: Data obtained from the Bureau of Economic Geology, U. S. Soil Conservation Service, and U. S. Geological Survey include geologic and soil data.
    6. Socio-economic Resources: Census data organized by the standard metropolitan statistical area (SMSA) are available.
  • Offers a variety of technical services to the public and various government offices. Most prominent is the Laboratory Services for water analyses. The laboratory has NELAP accredation for certain analysis. In addition, the laboratory is accredited to perform bacteriological testing of water. The specialized water analyses available include standard chemical analyses for anions, cations, and metals; pesticides and other organic carbons and bacteriological analyses.


  • The Education Center seeks to improve public understanding of the Edwards Aquifer through:

    1. the development and the dissemination of educational materials to the public
    2. the development and implementation of educational programs
      Examples include:
      • Curriculum development for public schools
      • In-service training for science teachers
      • Materials for local units of government

    Materials and services provided through the EARDC Education Center include:

    1. Seminars and workshops for educational groups and local units of government: On-site presentations are conducted for teachers, administrators, students and personnel from cities, counties and water supply districts in the aquifer region.
    2. Talks: Scheduled talks ranging from proper lawn irrigation to the unique fauna of the aquifer are given to organized groups in the area.
    3. Educational materials: Slide-tape presentations and booklets on water conservation have been produced for all grade levels. Materials on geography, hydrogeology and biology of the Edwards Aquifer are also available.
    4. Aquatic studies field days for educational groups: Activities include a discussion and viewing of films on groundwater, the Edwards Aquifer and the San Marcos River; a discussion and hands-on experience of water sampling, sampling for plant and animal specimens in the San Marcos River, and microscopic identification of invertebrate specimens.
    5. Aquatic Adventure Camp: This summer camp is offered every year in 6-day sessions for children ages 9 to 15. Also available are 2-day mini adventure camps.  Activities include aquatic studies each morning; scuba diving and swimming in the San Marcos River; tubing on the San Marcos River; raft trip on the Guadalupe River; visiting Natural Bridge Caverns,the Comal Springs and cave exploration.
  • Conducts basic and applied research related to the aquifer in the area of aquatic biology, geochemistry and hydrogeology. Previous subjects of environmental research included:

    • Groundwater quality in prairie wells
    • Hazardous waste sites
    • Innovative treatment of wastewater
      Water quality study (heavy metals - Cd and Pb) in Blue Wing Lakes-Bexar County
    • Wimberley water quality study
      Effects of waste water discharge from the proposed North San Marcos Waste Water Treatment Plant to the San Marcos River
    • Optimal groundwater management models for the Barton Springs - Edwards Aquifer
      Greywater Study for the university
    • San Marcos River management study
    • Edwards Aquifer ecosystem study
    • A two-layer model to simulate floating free product recovery
    • Optimal strategy for recovery of free product hydrocarbons
    • Seco watershed bioassessment study
    • A linear-lumped parameter model for real-time simulation of the Edwards Aquifer
    • Integrating groundwater contaminant transport with EPICWQ (Erosion - Productivity Impact Calculator) and SWRRBWQ (Simulator for Water Resources in Rural Basins) models

EARDC Analytical Laboratory Servicesnelac accredited lab

The Edwards Aquifer Research and Data Center (EARDC) has been providing water analysis services since 1979. Samples are analyzed from wells, springs, rivers, municipalities, and wastewater treatment facilities for a variety of chemical and biological constituents. The EARDC laboratory is accredited through National Environmental Laboratory Accreditation Conference (NELAC) by the Texas Commission on Environmental Quality (TCEQ). EARDC has provided a wide range of services for private citizens and numerous organizations including the Edwards Underground Water District, Environmental Protection Agency (EPA), Barton Springs Conservation District, Texas Parks and Wildlife Department (TP&W), Texas Water Development Board (TWDB), and Texas Commission on Environmental Quality (TCEQ).

Quality Assurance and Quality Control

EARDCs commitment is to meet our client’s requirements by providing a high caliber of environmental and laboratory services. The goal of the EARDC laboratory is to generate an error-free environment. The quality assurance and management system at EARDC stresses training and planning which yields increased personal performance, improved laboratory management and the prevention of errors. Our program relies on clearly defined objectives, well documented procedures, a comprehensive audit system and assistance of the EARDC management for its effectiveness.   The EARDC Quality Assurance program ensures that data produced is scientifically sound, legally defensible, and of known documentable and verifiable quality.