Report 276 OCCURRENCE, A VAILABILITY, AND QUALITY OF GROUND WATER IN TRA VIS COUNTY, TEXAS TEXAS D : PARTMENT OF WATER RESOURCES June 1983 TEXAS DEPARTMENT OF WATER RESOURCES REPORT 276 OCCURRENCE, AVAILABILITY, AND QUALITY OF GROUND WATER IN TRAVIS COUNTY, TEXAS Gunnar Brune and Gail L. Duffin Geologists June 1983 ---____ TEXAS DEPARTMENT OF WATER RESOURCES Charles E. Nemir, Executive Director TEXAS WATER DEVELOPMENT BOARD Louis A. Beecherl Jr., Chairman George W. McCleskey, Vice Chairman Glen E. Roney Lonnie A. “Bo” Pilgrim W. 0. Bankston Louie Welch TEXAS WATER COMMISSION Felix McDonald, Chairman Lee B. M. Biggart, Commissioner John D. Stover, Commissioner Authorization for use or reproduction of any original material contained in this publication, i.e., not obtained from other sources, is freely granted. The Department would appreciate acknowledgement. Published and distributed by the Texas Department of Water Resources Post Office Box 13087 Austin, Texas 78711 ii - ___------_____ TABLE OF CONTENTS Page CONCLUSIONS. 1 INTRODUCTION ............. 0 • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 3 Purpose and Scope ........ 0 • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 3 Location and Extent ....... 0 • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 4 Topography and Drainage .. 0 • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 4 Climate .................. 0................................................ 5 Population and Economy .. 0................................................ 6 Previous Investigations. 7 Methods of Investigation ................................................... 8 Well-Numbering System. 8 Acknowledgements ....... ,0 • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 10 Definitions of Terms ....... ,0 • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 11 GEOLOGY AS RELATED TO THE OCCURRENCE OF GROUND WATER. 12 History... ... .... .... ... .. ... .... .... .... .... ... .. .. .. .. .. .. ....... 12 Stratigraphy. 13 Structure. 15 STRATIGRAPHY OF THE WATER-BEARING UNITS. .. 20 Pre-Cretaceous Rocks. 20 Trinity Group Aquifer. 21 Lower Trinity. 21 iii TABLE OF CONTENTS-Continued Page Hosston Member of the Travis Peak Formation ...................... 21 Sligo Member of the Travis Peak Formation. 25 Hammett Shale Member of the Travis Peak Formation ............... 25 Middle Trinity ....... 25 Cow Creek Limestone Member of the Travis Peak Formation ......... 25 Hensell Sand Member of the Travis Peak Formation ................. 33 Lower Member of the Glen Rose Formation. 33 Upper Trinity. 33 Upper Member of the Glen Rose Formation. .. .. .. ... .... .. ..... 34 Paluxy Formation. 34 Edwards and Associated Limestones ........................................ 34 Austin Chalk. ... .. .. ... ... ... ... .... .... .. .. ... .. 35 Igneous Rocks . 39 Taylor and Navarro Groups ................................................. 39 Quaternary System ........................................................ 40 GENERAL GROUND-WATER HYDROLOGY. .. .. .. .. .. .. .. .. 40 Hydrologic Cycle. 40 Source and Occurrence .................................................... 41 Recharge, Movement, and Discharge. .. .... .. .. .... .... .... .... .. ... 42 Hydraulic Characteristics. 42 FI uctuations of Water Levels. 43 CHEMICAL QUAL.ITY . .. 44 General Chemical Quality or Standards. 44 iv TABLE OF CONTENTS-Continued Page Public Supply.... .. .. .. ..... .. ... .. .... ... ... ...... .. ........ 51 Primary Standards ................................................ 51 Secondary Standards. 53 Domestic and Livestock. .. .... .. .... .... .... .... .... .... ... ..... 54 Irrigation. 55 Industrial ............................................................. 56 OCCURRENCE AND AVAILABILITY OF GROUND WATER..................... 57 Trinity Group Aquifer. 57 Source and Occurre,nce . 57 Recharge, Movement, and Discharge. 58 Hydraulic Characteristics. 63 Changes in Water Levels. 66 Chemical Quality .. 69 Utilization and Development. 70 Availability of Ground Water for Development ........................... 71 Edwards and Associated Limestones Aquifer. 73 SClurce and Occurrence. 73 Recharge, Movement, and Discharge. 73 Hydraulic Characteristics. 78 Changes in Water Levels. .. ... ... .... ... .... ... ..... ........ ..... ... 78 Ctlemical Quality. .. .. ... 81 Utilization and Development. 82 Availability of Ground Water for Development ........................... 83 v TABLE OF CONTENTS-Continued Page Alluvium and Terrace Deposits. 84 Source and Occurrence. 84 RechargE!, Movement, and Discharge. 84 Hydraulic: Characteristics .... " . 84 Changes in Water Levels. 85 Chemical Quality . 85 Utilization and Development. 89 Availability of Ground Water for Development ........................... 89 Other Aquifers. 90 GROUND-WATER PROBLEMS . .... ~ . 91 Well Construction and Completion .......................................... 91 Ground-Water Contamination. 93 AREAS FAVORABLE FOR POTENTIAL GROUND-WATER DEVELOPMENT. 94 RECOMMENDATIONS. .. 97 SELECTED REFERENCES. .. .. 99 TABLES 1. Geologic Units and Their Water-Bearing Properties .......................... 14 2. Source, Significance, and Concentration of Dissolved-Mineral Constituents and Properties of Water. 45 3. Results of Pumping Tests. 64 4. Estimated Ground-Water Pumpage, 1955-76 . 72 5. Records of Wells, Test Holes, and Springs in Travis and Adjacent Counties. 104 vi TABLE OF CONTENTS-Continued Page 6. Records of Water Levels in Selected Wells in Travis and Adjacent Counties. 154 7. Records of Chemical Analyses of Water from Selected Wells, Test Holes, and Springs in Travis and Adjacent Counties. ..