Data Series 230

In cooperation with the Texas Parks and Wildlife Department

Compilation of Historical Water-Quality 

Data for Selected Springs in Texas, 

by Ecoregion
Cover. One orifice of Comal Springs in Landa Park at New Braunfels, Texas.
Compilation of Historical Water-Quality 

Data for Selected Springs in Texas, 

by Ecoregion

By Franklin T. Heitmuller and Iona P. Williams 

In cooperation with the Texas Parks and Wildlife Department 

Data Series 230

U.S. Department of the Interior

U.S. Geological Survey
U.S. Department of the Interior

DIRK KEMPTHORNE, Secretary

U.S. Geological Survey

Mark D. Myers, Director

U.S. Geological Survey, Reston, Virginia: 2006

For more information about the USGS and its products:

Telephone: 1-888-ASK-USGS

World Wide Web: http://www.usgs.gov/

Any use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply 

endorsement by the U.S. Government.

Although this report is in the public domain, permission must be secured from the individual copyright owners to 

reproduce any copyrighted materials contained within this report.

Suggested citation:

Heitmuller, F.T., and Williams, I.P., 2006, Compilation of historical water-quality data for selected springs in Texas, by 

ecoregion: U.S. Geological Survey Data Series 230, 32 p.
 iii

Contents

Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Purpose and Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Review of Existing Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Procedures for Data Compilation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Spring and Spring-Flow Database . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Springs Categorized by Ecoregions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Spring Survey for Selected Stakeholders in Texas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Application of Criteria to Selected Springs for Water-Quality Database . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Spring Water-Quality Database . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Historical Water-Quality Data for Selected Springs, by Ecoregion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Arizona/New Mexico Mountains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Chihuahuan Deserts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

High Plains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Southwestern Tablelands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Central Great Plains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Cross Timbers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Edwards Plateau . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Southern Texas Plains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Texas Blackland Prairies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

East Central Texas Plains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Western Gulf Coastal Plain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

South Central Plains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Database of Selected Springs in Texas (online only) 

available at . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . http://pubs.usgs.gov/ds/2006/230/

Figures

1. Map showing locations of selected springs in Texas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

2. Excerpt of survey mailed to numerous stakeholders across Texas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

3–6. Maps showing: 

3. Springs selected for inclusion in the water-quality database of springs in Texas, 

by ecoregion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

4. Major aquifers in Texas and springs selected for inclusion in the water-quality 

database of springs in Texas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

5. Minor aquifers in Texas and springs selected for inclusion in the water-quality 

database of springs in Texas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

6. River basins in Texas and springs selected for inclusion in the water-quality database 

of springs in Texas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

7. Screen capture of data-entry interface for water-quality database of springs in Texas . . . . . . . . . . . 11
iv 

8–25. Maps showing: 

8. Spatial distribution of 11,675 water-quality values for selected springs in Texas, by 

ecoregion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

9. Range of median silica concentrations for selected springs in Texas, by ecoregion . . . . . . . . . 12

10. Range of median calcium concentrations for selected springs in Texas, by 

ecoregion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

11. Range of median magnesium concentrations for selected springs in Texas, by 

ecoregion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

12. Range of median sodium concentrations for selected springs in Texas, by 

ecoregion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

13. Range of median potassium concentrations for selected springs in Texas, by 

ecoregion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

14. Range of median strontium concentrations for selected springs in Texas, by 

ecoregion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

15. Range of median bicarbonate concentrations for selected springs in Texas, by 

ecoregion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

16. Range of median sulfate concentrations for selected springs in Texas, by 

ecoregion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

17. Range of median chloride concentrations for selected springs in Texas, by 

ecoregion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

18. Range of median fluoride concentrations for selected springs in Texas, by 

ecoregion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

19. Range of median nitrate nitrogen concentrations for selected springs in Texas, by 

ecoregion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

20. Range of median pH for selected springs in Texas, by ecoregion . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

21. Range of median dissolved solids concentrations for selected springs in Texas, by 

ecoregion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

22 Range of median alkalinity for selected springs in Texas, by ecoregion . . . . . . . . . . . . . . . . . . . . . 19

23. Range of median hardness for selected springs in Texas, by ecoregion . . . . . . . . . . . . . . . . . . . . 19

24. Range of median specific conductance for selected springs in Texas, by ecoregion . . . . . . . . 20

25. Range of median temperature for selected springs in Texas, by ecoregion . . . . . . . . . . . . . . . . . 20

Tables

1. Number and percentage of total springs in database for Texas level III ecoregions . . . . . . . . . . . . . . . . 4

2. Largest springs in each Texas level III ecoregion on basis of mean spring flow for entire 

period of record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

3. Largest springs in Texas on basis of mean spring flow for entire period of record . . . . . . . . . . . . . . . . . . 6

4. Texas springs selected for water-quality and spring-flow database . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

5. Number of values used to compute mean, median, and standard deviation of selected 

water-quality constituents and properties for selected springs in Texas, by ecoregion . . . . . . . . . . . . 29

6. Water-quality parameter codes and description of selected constituents and properties 

used in statistical summaries and maps for selected springs in Texas . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

7. Mean, median, and standard deviation values of selected water-quality constituents 

and properties for selected springs in Texas, by ecoregion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

8. Minimum and maximum values of selected water-quality constituents and properties 

for selected springs in Texas, by ecoregion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

9. Water-quality standards of selected constituents and properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
 v

Conversion Factors and Datum

SI to Inch/Pound

Temperature in degrees Celsius (°C) may be converted to degrees Fahrenheit (°F) as follows:

°F=(1.8×°C)+32

Specific conductance is shown in microsiemens per centimeter at 25 degrees Celsius (μS/cm).

Concentrations of chemical constituents in water are shown in either milligrams per liter (mg/L) 

or micrograms per liter (μg/L).

Horizontal Datum

Horizontal coordinate information is referenced to the North American Datum of 1983 (NAD 83). 

Multiply By To obtain

Length

kilometer (km) 0.6214 mile (mi)

Area

square kilometer (km2) 0.3861 square mile (mi2)

Flow rate

cubic meter per second (m3/s) 70.07 acre-foot per day (acre-ft/d) 

cubic meter per second (m3/s) 35.31 cubic foot per second (ft3/s)

liter per second (L/s) 15.85 gallon per minute (gal/min) 
Blank Page
Compilation of Historical Water-Quality 

Data for Selected Springs in Texas, 

by Ecoregion

By Franklin T. Heitmuller and Iona P. Williams

Abstract

Springs are important hydrologic features in Texas. A 

database of about 2,000 historically documented springs and 

available spring-flow measurements previously has been compiled and published, but water-quality data remain scattered in 

published sources. This report by the U.S. Geological Survey, 

in cooperation with the Texas Parks and Wildlife Department, 

documents the compilation of data for 232 springs in Texas on 

the basis of a set of criteria and the development of a waterquality database for the selected springs. The selection of 

springs for compilation of historical water-quality data in Texas 

was made using existing digital and hard-copy data, responses 

to mailed surveys, selection criteria established by various 

stakeholders, geographic information systems, and digital database queries. Most springs were selected by computing the 

highest mean spring flows for each Texas level III ecoregion. A 

brief assessment of the water-quality data for springs in Texas 

shows that few data are available in the Arizona/New Mexico 

Mountains, High Plains, East Central Texas Plains, Western 

Gulf Coastal Plain, and South Central Plains ecoregions. Waterquality data are more abundant for the Chihuahuan Deserts, 

Edwards Plateau, and Texas Blackland Prairies ecoregions. 

Selected constituent concentrations in Texas springs, including 

silica, calcium, magnesium, sodium, potassium, strontium, sulfate, chloride, fluoride, nitrate (nitrogen), dissolved solids, and 

hardness (as calcium carbonate) are comparatively high in the 

Chihuahuan Deserts, Southwestern Tablelands, Central Great 

Plains, and Cross Timbers ecoregions, mostly as a result of subsurface geology. Comparatively low concentrations of selected 

constituents in Texas springs are associated with the Arizona/New Mexico Mountains, Southern Texas Plains, East 

Central Texas Plains, and South Central Plains ecoregions.

Introduction 

Springs and seeps are natural features in the bedrock or soil 

that function as discrete or clustered outlets to convey ground 

water to the surface. Ground water discharges through one orifice, multiple orifices, or seeps in the rock or soil. Springs commonly occur on hill slopes or valleys where a permeable rock 

unit overlies relatively impermeable strata, or along faults 

where a permeable rock unit is offset and abuts an impermeable 

unit. Other springs are the result of emergent alluvial underflow, karst features, or geothermal activity. Some areas are 

characterized by a high spatial density of springs; these include 

karstic environments, faults expressed at the land surface, valleys, and escarpments. Springs commonly form the head of a 

stream valley, a knickpoint of upstream valley incision, or a vertical step in streambed elevation.

Spring flow commonly is a substantial or even primary 

contributor to the base flow of rivers and streams. In particular, 

during drought conditions, springs account for almost the entire 

flow along some river reaches. Springs often flow at a constant 

rate if sourced by a relatively large ground-water recharge area 

or by an aquifer of low transmissivity (Brune, 1981). Fluctuations in spring flow can be attributed to either climatic conditions or ground-water withdrawals, and flow variation is 

exaggerated for springs with small recharge areas of high transmissivity (Brune, 1981). Water-quality data for spring flow can 

be used to determine flow paths and rock units that were in contact with the ground water (Cartwright and others, 2002; Grasby 

and others, 2000). For example, a dissolved solids concentration of 1,000 milligrams per liter or more might indicate long 

residence times or sulfur or halite deposits beneath the surface. 

The temperature of spring water can indicate the depth of the 

water source (Brune, 1981), such that springs near the mean 

annual surface temperature have shallow flow paths relative to 

springs warmer than mean annual surface temperature.

The importance of springs in identifying the sites of human 

habitation is evident from prehistoric artifacts that have been 

found at numerous springs across Texas (Brune, 1981; Shiner, 

1983). Sites near springs were originally selected to provide a 

water supply for many cities in Texas, including Austin, Big 

Spring, Brackettville, Del Rio, Dickens, Fort Stockton, Jacksboro, Lampasas, New Braunfels, Salado, San Antonio, San 

Marcos, Uvalde, and Waco. Historical forts in Texas located 
2 Compilation of Historical Water-Quality Data for Selected Springs in Texas, by Ecoregion

near springs include Fort Clark, Fort McKavett, Fort Richardson, and Fort Stockton.

Springs also serve as habitat for numerous species (Hubbs, 

2001). Many springs in Texas are habitat for endangered or 

threatened species or both: for example the Barton Springs salamander (Eurycea sosorum), Texas wild rice (Zizania texana) 

downstream of San Marcos Springs in San Marcos, and the 

fountain darter (Etheostoma fonticola) in Comal Springs in 

New Braunfels. In West Texas, the Comanche Springs pupfish 

(Cyprinodon elegans) resides in San Solomon Spring; Comanche Springs generally has been dry since 1962 (Brannan and 

others, 2003).

In Texas, springs are a highly visible component of the 

hydrologic cycle. Federal and State agencies, resource conservation groups, water managers, municipalities, landowners, and 

even people who use springs or spring-fed rivers for recreation 

give close attention to the quantity and quality of water discharging from springs. From the perspective of many individuals and entities, springs serve as an indicator of the quality and 

availability of ground water (Bonacci, 1995).

In 2003, the U.S. Geological Survey (USGS), in cooperation with the Texas Water Development Board (TWDB), 

published a database of Texas springs and spring-flow measurements (Heitmuller and Reece, 2003). Data sources for this 

database were limited, however, to digital spreadsheets from 

the TWDB and Capitol Environmental Services, the USGS 

National Water Information System (NWIS), and hard-copy 

annual Water-Data Reports and Water-Supply Papers of the 

USGS. Heitmuller and Reece (2003) represents only springs 

with verified geographic coordinates in Texas; the authors of 

that publication acknowledge the existence of many springs not 

included in the database.

Following the publication of Heitmuller and Reece (2003), 

a series of meetings were held at the USGS office in Austin, 

Texas, between December 2003 and March 2004 to organize 

further investigative efforts related to springs in Texas. Participants in the meetings represented the interests of Federal and 

State agencies, nonprofit organizations, universities, research 

centers, and private landowners. One outcome of the meetings 

was a project by the USGS, in cooperation with the Texas Parks 

and Wildlife Department, to select primary springs in Texas and 

compile existing water-quantity and water-quality data for 

those springs into a database. The database then would serve as 

a platform for future water-quality and spring-flow monitoring. 

The selection of springs would be based on criteria that include 

spring flow, historical and cultural importance, water use, habitat to unique species, and linkage to aquifers or streamflow. An 

important consideration in the scope of the work was to ensure 

an adequate regional representation of springs.

Purpose and Scope

The purpose of this report is to document the compilation of a water-quality database for selected primary springs 

throughout Texas. The report also documents the sources and 

procedures used to select springs for the water-quality database 

and provides maps of selected constituents and explanations of 

spring water quality for level III Texas ecoregions. Level III 

ecoregions are land areas identified by the U.S. Environmental 

Protection Agency (2004) with similar geology, physiography, 

vegetation, climate, soils, land use, and hydrology (Griffith and 

others, 2004).

Review of Existing Data

Before 1894, no systematic data collection was done on 

springs in Texas, although a few discrete pre-1894 spring-flow 

estimates are available. The first systematic data collection on a 

Texas spring was in 1894, when the USGS began to monitor the 

flow of Barton Springs in Austin. Spring-flow monitoring on 

other major Texas springs began soon thereafter, in 1895, at 

Comal Springs in New Braunfels, Las Moras Springs in Brackettville, and San Felipe Springs in Del Rio. The next documentation of springs and spring flow in Texas was done in the 1940s 

and 1950s by the Texas Board of Water Engineers (TBWE), 

now the TWDB. Records of wells and springs were published 

by county in TBWE ground-water resources reports (see Baker, 

2005). These records contain spring names, owners, aquifer 

associations, and discrete spring-flow and water-quality 

measurements. The TWDB continued the compilation of spring 

records by county beginning in 1957. Additionally, a study of 

the geohydrology of Comal, San Marcos, and Hueco Springs 

(William F. Guyton & Associates, 1979) was sponsored by the 

TWDB.

The most substantial springs and spring-flow documentation in Texas was done by Gunnar Brune in the 1970s. Brune 

(1975) presents site information, water quality, and spring-flow 

declines for 281 major and historical Texas springs. This report 

was a prelude to Brune (1981), a detailed compilation of all 

known springs in 183 counties in Texas. In addition to written 

accounts of visits to these springs, many spring-flow and waterquality measurements are provided. Currently (2006), a publication of springs for the remaining counties is not available.

Acknowledgments

The authors are grateful to Larry McKinney, Cindy 

Loeffler, Chad Norris, and David Bradsby of the Texas Parks 

and Wildlife Department for providing information and helpful 

suggestions during preparation of this report.

Procedures for Data Compilation

The selection of springs for compilation of historical 

water-quality data in Texas was made using existing digital 

and hard-copy data, responses to mailed surveys, selection 

criteria established by various stakeholders, geographic information systems (GIS), and various database queries. Field and 

laboratory work were not a component of this compilation; 

sources were limited to previously published data.
Procedures for Data Compilation 3

26o00'

28o

00'

30o

00'

32o

00'

106o

00' 104o

00'

34o

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36o

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102o

00' 100o

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98o

00' 96o

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94o

00'

Base modified from Texas Natural Resources

Information System (TNRIS) digital data, 2005,

1:24,000

Albers equal area projection parameters

Central meridian: -100.0

Standard parallel 1: 34.91666667

Standard parallel 2: 27.41666667

Latitude of origin: 31.16666667 

EXPLANATION

Spring

0 90 180 270 360 KILOMETERS

Figure 1. Locations of selected springs in Texas (from Heitmuller and Reece, 2003).

Spring and Spring-Flow Database

The primary data source for spring and spring-flow information is Heitmuller and Reece (2003), which contains geographic coordinates, spring names, site information, and known 

spring-flow measurements. Heitmuller and Reece (2003) contains 2,061 springs (fig. 1) and more than 7,300 spring-flow 

measurements, not including daily spring-flow values from 

USGS continuous-record gaging stations. Following the release 

of Heitmuller and Reece (2003), 1,895 spring-flow measurements from Brune (1975, 1981) were added to the database. The 

inclusion of these data into Heitmuller and Reece (2003) 

required an analysis and removal of duplicate flow measurements. The result was a comprehensive database of all known 

springs and spring-flow measurements in Texas. This comprehensive database of springs and spring-flow measurements is 

the source of the data used for analysis of spring flow for this 

report.

The comprehensive database of spring-flow measurements 

was used to compute mean spring flow of all springs. For the 

few springs that are continuously monitored, including Comal, 

San Marcos, and Barton Springs, the mean data published in 

volumes 1–5 of USGS “Water Resources Data, Texas, Water 

Year 2004” (Aragon Long and others, 2005) were used. For 

other springs that comprise multiple orifices, an effort was 

made to compute combined mean spring flow. Examples 

include Leona Springs in Uvalde County and Salado Springs in 

Bell County, among others. This is consistent with methods 

used by the USGS and Brune (1975, 1981). No-flow measurements for the period of record also were used to compute mean 

spring flow.

Springs Categorized by Ecoregions

Springs in the comprehensive database were categorized 

into 12 level III ecoregions associated with Texas (table 1). As 

summarized by Griffith and others (2004), “Ecoregions denote 

areas of general similarity in ecosystems and in the type, quality, and quantity of environmental resources,” and “ecological 

regions are hierarchical and can be identified through the analysis of the spatial patterns and the composition of biotic and abiotic phenomena that affect or reflect differences in ecosystem 

quality and integrity.” Level III ecoregions in Texas were developed to serve as a spatial framework for assessment of ecosystems (U.S. Environmental Protection Agency, 2004). Areas 

within each Texas level III ecoregion have similar geology, 

physiography, vegetation, climate, soils, land use, wildlife, and 

hydrology (Griffith and others, 2004). Level III ecoregions 

were chosen as a regional framework for assessment of Texas 

springs because (1) the entire State is represented, (2) all springs 

can be associated with an ecoregion, and (3) the differences in 

geology, physiography, hydrology, and other factors between 

ecoregions should be reflected in the water quality of springs. 

The number of level III ecoregions in Texas, therefore, reflects 
4 Compilation of Historical Water-Quality Data for Selected Springs in Texas, by Ecoregion

the desired diversity and level of regional assessment. Aquifers 

were not used to categorize springs because not all springs 

emerge from a State-of-Texas-designated aquifer. River basins 

were not used to categorize springs because river basins can 

extend across a number of ecoregions.

A limitation of the ecoregion categorization is that some 

springs with relatively long flow paths or large recharge areas 

emerge in a different ecoregion than the ecoregion contributing 

the water. For example, this limitation is particularly evident 

along relatively sharp ecoregion boundaries, including the 

Caprock escarpment between Ecoregions 25 and 26 and the 

Balcones escarpment between Ecoregions 30, 31, and 32. The 

water quality of large springs in Ecoregions 31 and 32, including Comal, San Marcos, Barton, San Antonio, San Felipe, and 

Las Moras Springs, is correctly associated with the carbonate 

hydrogeology of Ecoregion 30 (Edwards Plateau). The water 

quality of numerous springs included in Ecoregion 26 is correctly associated with the Ogallala aquifer in Ecoregion 25 

(High Plains). Additionally, the scale at which ecoregion 

boundaries are digitally represented is not sufficient to capture 

every detail of the actual landscape. For example, the boundary 

between Ecoregions 25 and 26 is straighter than the actual 

Caprock escarpment, effectively crossing the escarpment many 

times. As a result, some springs below the escarpment are 

assigned to Ecoregion 25 (High Plains), and others are assigned 

to Ecoregion 26 (Southwestern Tablelands). Regional waterquality assessments are presented for the digital ecoregions 

because of the ease that GIS provides in assigning springs. Furthermore, the region to which the spring contributes surface 

flow also is hydrologically connected to the spring.

Some ecoregions are relatively dry, flat, or not spatially 

extensive and do not have many springs; other ecoregions are 

relatively wet, sloped, or spatially extensive and have many 

springs. For example, Ecoregion 34 (Western Gulf Coastal 

Plain) is relatively flat and is represented by only 16 springs in 

the database. However, the highly conductive (to flow) hydrology and relatively steep topography of Ecoregion 30 (Edwards 

Plateau) is represented by 818 springs in the comprehensive 

database. The number of springs for each ecoregion was divided 

by the total number of springs in the database to determine the 

percentage of springs in each ecoregion (table 1).

Following categorization of springs into level III ecoregions, the largest springs within each ecoregion (table 2) were 

ranked by mean spring flow. The 10 largest springs in Texas are 

listed in table 3. The order generally agrees with the ranking of 

Brune (1981). The lower ranking of Comanche Springs reflects 

a number of no-flow measurements made since 1981. The rankings in tables 2 and 3 are somewhat tenuous, however, as mean 

spring flow was computed from available measurements. 

Comal, Barton, and San Marcos Springs have continuous flow 

data, some springs have hundreds of discrete measurements, 

and other springs have very few discrete measurements over 

short periods of record.

Spring Survey for Selected Stakeholders in Texas

The selection of springs for historical water-quality and 

spring-flow data entry and analysis for this report was facilitated by a survey (fig. 2) mailed to stakeholders across Texas. 

More than 400 surveys were sent to numerous Federal and State 

agencies, water districts, nonprofit organizations, and other 

Table 1. Number and percentage of total springs in database for Texas level III ecoregions (Heitmuller and Reece, 2003).

[km2, square kilometers] 

Ecoregion ID Ecoregion name

Ecoregion area

(km2

)

Number of springs 

in database

Percentage of all

springs in database

23 Arizona/New Mexico Mountains 219 3 0.15

24 Chihuahuan Desert 91,362 206 10.0

25 High Plains 84,063 43 2.09

26 Southwestern Tablelands 60,185 304 14.8

27 Central Great Plains 46,693 135 6.55

29 Cross Timbers 51,920 129 6.26

30 Edwards Plateau 74,963 818 39.7

31 Southern Texas Plains 53,492 36 1.75

32 Texas Blackland Prairies 43,381 107 5.19

33 East Central Texas Plains 54,809 149 7.23

34 Western Gulf Coastal Plain 59,787 16 .78

35 South Central Plains 63,977 115 5.58

TOTALS FOR TEXAS 684,851 2,061 100
Procedures for Data Compilation 5

Table 2. Largest springs in each Texas level III ecoregion on basis of mean spring flow for entire period of record. 

[Mean spring flow computed mostly from discrete measurements, but some time-averaged values used to extend period of record. m3/s, cubic meters per second]

1 Currently beneath surface of Lake Amistad.

2 Computed from monthly mean spring flow for period of record.

3 Now generally dry.

4 Includes numerous no-flow measurements.

5 Name derived from Texas State well number.

6 Based only on three measurements.

7 Computed from continuous daily spring flow.

Ecoregion

ID

Station 

number Spring name County Period of recordor year visited

Mean spring flow 

(m3

/s)

23 08407600 Smith Spring Culberson 1968–76 0.0024

24 108448500 Goodenough Springs Val Verde 1921–68 24.1342

08427500 San Solomon Springs Reeves 1900, 1904, 1919–25, 1931–36, 1941–86, 

1990, 1997, 2001–04

.8665

3

08444500 Comanche Springs Pecos 1899, 1904, 1919–25, 1932–84, 1992 4.8014

305331103013201 Leon Springs Pecos 1920, 1932–33, 1946–50, 1958, 1962, 1971 .3086

308425500 Phantom Lake Spring Jeff Davis 1900, 1904, 1931–34, 1941–2004 4

.2282

25 333230101423201 Buffalo Springs Lubbock 1907, 1924, 1937, 1939, 1969–76 .0665

26 343251100252201 Estelline Salt Springs Hall 1943, 1946, 1954, 1960–63 .1063

350727100085801 5DU–56–33–307 Collingsworth 1967 .0908

324530100423101 Camp Springs Scurry 1924 .0567

350749100174801 Elm Creek Spring no. 1 Collingsworth 1947–1978 .0556

350330100083201 Wolf Springs Collingsworth 1938, 1967, 1971, 1977 .0450

27 345918100204601 Wischkaemper Springs Collingsworth 1967, 1971, 1977 .0314

352430100061101 Wheeler Springs Wheeler 1967, 1971, 1977 .0180

345920100473001 5JA–12–02–304 Donley 1968 .0140

29 08146500 San Saba Springs San Saba 1939, 1952, 1957, 1959–2004 .2664

310320098110001 Hancock Springs Lampasas 1886, 1900–1902, 1906, 1910, 1924, 1931, 

1942, 1957–75

.2194

311213098543901 Baker Spring San Saba 1938, 1952, 1957, 1961–62, 1971, 1989 .1118

30 08168000 Hueco Springs Comal 1924, 1928–29, 1937, 1944–2003 1.1695

301619099523801 Big Paint Springs Edwards 1939, 1955, 1962 6.6700

1294031100563101 Slaughter Bend Springs Val Verde 1921, 1925, 1928, 1971, 1976 .6570

08149500 Seven Hundred Springs Edwards 1939, 1952, 1956, 1959–2004 .5658

293031098543101 Diversion Dam Springs Medina 1921, 1923–35, 1939, 1948, 1950–57, 1960, 

1962–1969

.5628

31 08452800 San Felipe Springs Val Verde 1889, 1895–1939, 1952–71, 1997 2.4579

08204000 Leona Springs Uvalde 1925, 1931, 1934–35, 1939, 1946–47, 1965–

74, 1976–2002

.6580

08456300 Las Moras Springs Kinney 1895–96, 1899–1900, 1902, 1904–06, 1910, 

1912, 1925, 1928, 1939–2000

.5802

32 08168710 Comal Springs Comal 1932–2004 78.1553

08170000 San Marcos Springs Hays 1956–2004 74.9272

08155500 Barton Springs Travis 1978–2004 71.8406

08177818 San Antonio Springs Bexar 1895–1963, 1970–2004 1.2658

08104300 Salado Springs Bell 1902–03, 1934, 1948, 1950–73, 1975, 1981 .5223

33 323030095533101 Riley Spring Van Zandt 1979 .0170

291657098020801 Sutherland Springs Wilson 1949, 1954, 1968 .0156

322117095545601 Roher Springs Henderson 1995 .0117

34 29343109423101 Smith Springs Galveston 1975 .0013

35 313331095313101 Elkhart Creek Springs Houston 1965 .0963

312731095323101 Hays Branch Springs Houston 1965 .0510

312731095303101 Houston 1965 .0500
6 Compilation of Historical Water-Quality Data for Selected Springs in Texas, by Ecoregion

water-resource entities in Texas. Emphasis was on surveying 

local recipients; most surveys were mailed to the distributed 

offices of larger agencies. Recipients included the Texas Parks 

and Wildlife Department, the Texas Commission on Environmental Quality, the Texas Water Development Board, the 

Texas Historical Commission, the Texas Department of Agriculture, regional water planning groups, ground-water conservation districts, river authorities, selected university faculty, 

numerous nonprofit organizations, and private individuals. Surveys were also sent to Federal agencies with a presence in 

Texas, including the USGS (Water Science Centers), U.S. Fish 

and Wildlife Service, and U.S. Department of Agriculture, Natural Resources Conservation Service.

The survey was designed for a flexible response and 

encouraged recipients to provide information on springs 

important to their jurisdiction or within their expertise. Relative 

importance could be attributed to large or persistent spring 

flow; historical or cultural significance; habitat for endangered, 

threatened, or other species of concern; water use; contribution 

to surface water; aquifer association; or other unique environmental characteristics. All survey responses were reviewed and 

tabulated; of 416 surveys mailed out, 54 responses were made 

through mail, e-mail, or phone. Of these, 34 reported no known 

springs or did not provide any specific springs in their response. 

However, the small number of responses, both with and without 

information on specific springs, represented a considerable 

variety of stakeholders across most of Texas. Fifty-eight springs 

were reported to match one or more elements of the criteria 

described above.

Application of Criteria to Selected Springs for WaterQuality Database

Springs primarily were selected for the water-quality 

database of this report by (1) mean spring-flow ranking and 

(2) spring-survey response. Springs with the highest mean 

spring flow were selected for each ecoregion. To ensure that all 

level III ecoregions were adequately represented in the database, the number of springs selected for each ecoregion corresponded to the percentage of all Texas springs in that ecoregion 

(table 1). This percentage was applied to a goal of about 

200 springs for the entire State; the goal of about 200 springs 

Table 3. Largest springs in Texas on basis of mean spring flow for entire period of record. 

[Mean spring flow computed mostly from discrete measurements, but some time-averaged values used to extend period of record. m3/s, cubic meters per second] 

Station

number Spring name County

Level III

ecoregion ID

Period of record

or year visited

Mean spring flow

(m3

/s)

08168710

08170000

2

08448500

Comal Springs

San Marcos Springs

Goodenough Springs

Comal

Hays

Val Verde

32

32

24

1932–2004

1956–2004

1921–68

1

8.1553

1

4.9272

34.1342

08452800

08155500

San Felipe Springs

Barton Springs

Val Verde

Travis

31

32

1889, 1895–1939, 1952–71, 1997

1978–2004

2.4579

11.8406

08177818 San Antonio Springs Bexar 32 1895–1963, 1970–2004 1.2658

08168000 Hueco Springs Comal 30 1924, 1928–29, 1937, 1944–2003 1.1695

08427500

4

08444500

301619099523801

San Solomon Springs

Comanche Springs

Big Paint Springs

Reeves

Pecos

Edwards

24

24

30

1900, 1904, 1919–25, 1931–36,

1941–86, 1990, 1997, 2001–04

1899, 1904, 1919–25, 1932–84, 1992

1939, 1955, 1962

.8665

5

.8014

6.6700

1 Computed from continuous daily spring flow.

2 Currently beneath surface of Lake Amistad.

3 Computed from monthly mean spring flow for period of record.

4 Now generally dry.

5 Includes numerous no-flow measurements.

6 Based on only three measurements.
Procedures for Data Compilation 7

Name: ________________________________________________

Organization: ________________________________________________

Location: ________________________________________________

Telephone: ________________________________________________

E-mail: ________________________________________________

Check all that apply. Please provide specific details under ‘Justification’, including name of species, aquifer name, 

use of water, and so forth, to the extent you are able. 

Spring: ________________________________________________

County: ________________________________________________

Importance: ___ Currently ___ Historically

Water-use Source of water to large river basins 

Importance to an aquifer 

 Unique environmental characteristics Other

Justification: ________________________________________________ 

________________________________________________________________

________________________________________________________________

________________________________________________

________________________________________________

________________________________________________

________________________________________________

________________________________________________

________________________________________________

________________________________________________

Regionally large spring flow 

Historically / culturally significant 

Habitat for endangered, threatened, or species of concern

________________________________________________

________________________________________________________________

________________________________________________________________

Figure 2. Excerpt of survey mailed to numerous stakeholders across Texas.

was established during stakeholder meetings between December 2003 and March 2004. For example, Ecoregion 24 (Chihuahuan Desert) contains 206 springs, or about 10 percent of all 

springs in the database. To ensure adequate representation in 

the water-quality database, about 10 percent of springs in 

Ecoregion 24 were selected, or 20 springs. Ecoregion 23 

(Arizona/New Mexico Mountains) was the only ecoregion that 

did not contain at least 1 percent of all Texas springs. Nonetheless, the largest spring in this ecoregion was selected. This 

method resulted in the selection of 209 springs.

Following the quantitative method of selecting springs on 

the basis of mean spring flow, qualitative methods were used to 

select additional springs. Eleven springs were selected on the 

basis of only the responses to mailed surveys, especially if the 

springs were mentioned in Brune (1975). Additionally, four 

springs that were not selected, but that the authors felt were 

important on the basis of history or recreational use, were added 

to the water-quality database. These included Hamilton Springs 

in Travis County, Krause Springs in Burnet County, Chinati 

Hot Springs in Presidio County, and Carrizo Springs in Dimmit 

County, among others.

Finally, for some large areas of the State not represented 

by the selected springs, the spring-flow database (Heitmuller 

and Reece, 2003) and spring-flow measurements from Brune 

(1975, 1981) were assessed to select the largest springs in those 

areas. Eight springs were selected by this method. For example, 
8 Compilation of Historical Water-Quality Data for Selected Springs in Texas, by Ecoregion

in north-central Texas a large area that includes parts of 

Ecoregions 27, 29, and 32 was not represented by any springs. 

For this area, four springs with the largest mean spring flow 

were chosen, including Buffalo Springs in Clay County, 

Browder Springs in Dallas County, PX–32–52–503 in Johnson 

County, and Pierson Spring in Bosque County.

A total of 232 springs were selected for inclusion in the 

water-quality database of this report (fig. 3; table 4, at end 

of report) using both quantitative and qualitative methods, 

including mean spring flow, responses to mailed surveys, Brune 

(1975), and judgment by the authors based on geographic 

coverage and other criteria. Most springs were chosen by an 

assessment of mean spring flow for each ecoregion. The springs 

represent all level III ecoregions in Texas, eight of nine major 

aquifers (fig. 4), 11 of 21 minor aquifers (fig. 5), and 16 of 23 

river basins in the State (fig. 6). Major and minor aquifers are 

those designated as such by the TWDB (Ashworth and 

Hopkins, 1995).

Spring Water-Quality Database

All selected springs and associated spring-flow measurements were entered into a new database. A table was created in 

this database to store water-quality data, including concentrations of selected constituents, specific conductance, pH, and 

temperature (fig. 7). Water-quality data were obtained from 

(1) TBWE hard-copy bulletins, (2) TWDB hard-copy reports, 

(3) Brune (1975, 1981), (4) the TWDB well information database (Texas Water Development Board, 2005), and (5) the 

USGS NWIS digital database (U.S. Geological Survey, 2001). 

TBWE bulletins are organized by county or river basin and contain data on wells and springs; most were published in the 1950s 

and early 1960s. TWDB reports are similar to TBWE bulletins 

and have been published from 1965 to the present (2006). Brune 

(1975, 1981) contains water-quality data for a number of 

springs. Measurements from the TWDB well information database were queried for the selected springs. The NWIS database 

serves as the storage for all hydrologic data of the USGS. All 

water-quality measurements were manually entered except 

those from the TWDB water-quality database and NWIS, which 

were digitally imported. Duplicate measurements in two or 

more sources were removed.

The temporal range in water-quality data for springs in 

Texas spans from the late 19th century to the present (2006). 

Sampling and laboratory techniques have changed considerably 

since the earliest samples and measurements were obtained, 

resulting in greater accuracy and precision of data in more 

recent years. Additionally, numerous water-quality measurements from the late 19th and early 20th centuries do not have 

quality-assurance or quality-control data available. Of more 

than 51,000 individual water-quality values in the database, 

about 11,500 measurements do not have quality-assurance 

codes. The water-quality assessments provided for each level 

III ecoregion in Texas include all available measurements, as 

temporal extension of the data was desired. For ecoregions with 

few data, some bias might be introduced through earlier waterquality samples obtained and measured with different technology. Seasonal bias also might be inherent because spring flow 

and associated concentrations of selected constituents vary with 

seasonal changes in precipitation and aquifer capacity. Database queries show that water quality of Texas springs has been 

sampled fairly consistently for each of the four seasons, even 

for ecoregions with few data.

Historical Water-Quality Data for Selected 

Springs, by Ecoregion

A total of 11,675 individual values for various waterquality constituents and properties (table 5, at end of report) 

were used to compute statistical summaries of water-quality 

data for selected springs in Texas. More than 50,000 individual 

values are provided in the database, the difference representing 

additional water-quality constituents, such as ammonia, cadmium, and many organic compounds that are not presented in 

this report. Water-quality constituents and properties used in the 

analyses and presented on maps are listed in table 6 (at end of 

report). A map of the spatial distribution of water-quality values 

for springs in each Texas ecoregion is shown in figure 8. Ecoregion 32 (Texas Blackland Prairies) has the highest number of 

values (5,387) because some of the largest and most frequently 

monitored springs in Texas issue from that ecoregion, including 

Comal, San Marcos, Barton, and San Antonio Springs. Ecoregion 23 (Arizona/New Mexico Mountains) has only 13 waterquality values because of its small size and associated representation in the database.

A brief assessment of the water-quality data is presented 

for each level III ecoregion in Texas. The mean, median, and 

standard deviation of water-quality constituents and properties 

for selected springs in Texas, by ecoregion, are listed in table 7 

(at end of report). Censored data, or data reported as less than a 

reporting level, were included as one-half the reporting level in 

the computation of summary statistics for each ecoregion. The 

minimum and maximum water-quality values, by ecoregion, 

are listed in table 8 (at end of report). Water-quality standards, 

mostly for drinking water, for selected constituents and properties are listed in table 9 (at end of report). Not all constituents 

and properties discussed in this report have water-quality standards. Maps showing the distribution of median water-quality 

values (table 7) are presented in figures 9–25. The authors recognize that some springs have considerably more water-quality 

data than others, which influences the summary statistics for 

each ecoregion. Of 1,474 visits for water-quality sampling 

entered in the database, five springs (Barton, Comal, Hueco, 

Old Mill, and San Marcos) account for 876 sampling visits. 

Barton Springs has the greatest number of sampling visits with 

479. As a result, water-quality summary statistics for Ecoregion 

32 (Texas Blackland Prairies) are greatly influenced.
Figure 3. Springs selected for inclusion in the water-quality database of springs in Texas, by ecoregion.

EXPLANATION

Level III Ecoregion ID and name

23–Arizona/New Mexico Mountains24–Chihuahuan Deserts25–High Plains26–Southwestern Tablelands27–Central Great Plains29–Cross Timbers

30–Edwards Plateau

Spring

31–Southern Texas Plains32–Texas Blackland Prairies33–East Central Texas Plains34–Western Gulf Coastal Plain35–South Central Plains

0 90 180 270 360 KILOMETERS

Base modified from Texas Natural ResourcesInformation System (TNRIS) digital data, 2005,1:24,000Albers equal area projection parametersCentral meridian: -100.0Standard parallel 1: 34.91666667Standard parallel 2: 27.41666667Latitude of origin: 31.16666667 

Ecoregions from U.S. EnvironmentalProtection Agency, 2004

26o00'

28o00'

30o00'

32o00'

106o00' 104o00'

34o00'

36o00'

102o00' 100o00'

98o00' 96o00'

94o00'

Fort Stockton

Del Rio

Brackettville/Fort Clark

Uvalde

San Antonio

New Braunfels

San Marcos

Austin

Salado

Lampasas

Fort 

McKavett

Balcones esca rpment

Caprock

esc

a

r

p

m

e

n

t

Guadalupe Mountains

National Park

Jacksboro/Fort 

Richardson

Dickens

Big Spring

Waco

Figure 4. Major aquifers in Texas and springs selected for quality database of springs in Texas.

26o00'

28o00'

30o00'

32o00'

106o00' 104o00'

34o00'

36o00'

102o00' 100o00'

98o0

0 90 180 270 360 KILOMETERS

Base modified from Texas Natural ResourcesInformation System (TNRIS) digital data, 2005,1:24,000Albers equal area projection parametersCentral meridian: -100.0Standard parallel 1: 34.91666667Standard parallel 2: 27.41666667Latitude of origin: 31.16666667 

EXPLANATION

Cenozoic Pecos alluviumSeymourGulf Coast Carrizo-Wilcox (outcrop)Carrizo-Wilcox (downdip)Hueco-Mesilla bolsonOgallalaEdwards-Trinity Plateau (outcrop)

Major aquifer

Outcrop is that part of a water-bearinthe land surface. Downdip is that parthat lies or dips below other rock lay

Edwards-Trinity PlaEdwards Balcones Edwards Balcones Trinity (outcrop)Trinity (downdip)

Spring
Figure 5. Minor aquifers in Texas and springs selected for inclusion in the waterquality database of springs in Texas.

26o00'

28o00'

30o00'

32o00'

106o00' 104o00'

34o00'

36o00'

102o00' 100o00'

98o00' 96o00'

94o00'

0 90 180 270 360 KILOMETERS

Base modified from Texas Natural ResourcesInformation System (TNRIS) digital data, 2005,1:24,000Albers equal area projection parametersCentral meridian: -100.0Standard parallel 1: 34.91666667Standard parallel 2: 27.41666667Latitude of origin: 31.16666667 

West Texas bolsonsLipanYegua JacksonIgneousSparta (outcrop)Sparta (downdip)Queen City (outcrop)Queen City (downdip)Nacatoch (outcrop)Nacatoch (downdip)Blossom (outcrop)Blossom (downdip)Woodbine (outcrop)Woodbine (downdip)Rita Blanca

Minor aquifer

EXPLANATION

Brazos River alluvium Edwards-Trinity (High Plains)

Dockum (outcrop)Dockum (downdip)

Rustler (outcrop)Rustler (downdip)Capitan Reef complexBlaine (outcrop)Blaine (downdip)Bone Spring-Victorio Peak

Ellenburger-San Saba (outcrop)Ellenburger-San Saba (downdip)Hickory (outcrop)Hickory (downdip)

Outcrop is that part of a water-bearing rock layer that appears at the land surface. Downdip is that part of a water-bearing rock layer that lies or dips below other rock layers.

Spring

Marble FallsMarathon

Geology from Texas WaterDevelopment Board, 1990

Figure 6. River basins in Texas and springs selected for indatabase of springs in Texas.

26o00'

28o00'

30o00'

32o00'

106o00' 104o00'

34o00'

36o00'

102o00' 100o00'

98o00' 

0 90 180 270 360 KILOMETERS

Base modified from Texas Natural ResourcesInformation System (TNRIS) digital data, 2005,1:24,000Albers equal area projection parametersCentral meridian: -100.0Standard parallel 1: 34.91666667Standard parallel 2: 27.41666667Latitude of origin: 31.16666667 

River basin

EXPLANATION

CanadianRedSulphurCypressSabineNechesNeches-TrinityTrinityTrinity-San JacintoSan JacintoSan Jacinto-BrazosBrazosBrazos-ColoradoColoradoColorado-LavacaLavaca

Spring

San AntonioSan Antonio-NuecesNuecesNueces-Rio GrandeRio GrandeLavaca-GuadalupeGuadalupe
Historical Water-Quality Data for Selected Springs, by Ecoregion 11

Figure 7. Screen capture of data-entry interface for water-quality database of springs in Texas.

Arizona/New Mexico Mountains

The Arizona/New Mexico Mountains (Ecoregion 23) is 

represented by one spring in the water-quality database, Smith 

Spring. The inclusion of only one spring is attributed to the very 

small area of the ecoregion (219 square kilometers) in Texas 

and the availability of only three springs in the database. Smith 

Spring in Guadalupe Mountains National Park issues from the 

Capitan Reef Complex aquifer, associated with a Permian carbonate reef platform (Ashworth and Hopkins, 1995) in the 

Guadalupe Mountains. Analysis of one sample from Smith 

Spring shows a dissolved solids concentration of 299 milligrams per liter, calcium concentration of 76 milligrams per liter, 

and bicarbonate concentration of 358 milligrams per liter. The 

concentrations of silica (10 milligrams per liter), sodium (2 milligrams per liter), and chloride (2 milligrams per liter) were 

lower than mean concentrations in selected springs of the other 

Texas level III ecoregions.

Chihuahuan Deserts

The Chihuahuan Deserts (Ecoregion 24) is represented 

by 29 springs in the water-quality database. A few of the 

selected springs in the Chihuahuan Deserts have comparatively 

long (Uliana and Sharp, 2001) or deep flow paths and spring 

waters characterized by high median concentrations of constituents and warm temperatures. Selected springs in the Chihuahuan Deserts have the highest median concentrations of calcium (177 milligrams per liter), magnesium (73 milligrams 

per liter), sodium (390 milligrams per liter), potassium (17 milligrams per liter), strontium (3.4 milligrams per liter), sulfate 

(383 milligrams per liter), chloride (246 milligrams per liter), 

fluoride (1.7 milligrams per liter), dissolved solids (1,343 milligrams per liter), and hardness as calcium carbonate (514 milligrams per liter) of all the level III ecoregions in Texas. Additionally, median specific conductance (3,220 microsiemens per 

centimeter at 25 degrees Celsius) and temperature (25 degrees 

Celsius) were the highest among springs of the level III 

ecoregions.
Figure 8. Spatial distribution of 11,675 water-quality values for selected springs in Texas, by ecoregion.

0 90 180 270 360 KILOMETERS

Base modified from Texas Natural ResourcesInformation System (TNRIS) digital data, 2005,1:24,000Albers equal area projection parametersCentral meridian: -100.0Standard parallel 1: 34.91666667Standard parallel 2: 27.41666667Latitude of origin: 31.16666667 

Ecoregions from U.S. EnvironmentalProtection Agency, 2004

26o00'

28o00'

30o00'

32o00'

106o00' 104o00'

34o00'

36o00'

102o00' 100o00'

98o00' 96o00'

94o00'

32

32

25

25

26

26

27

27

23

24

30

30

31

29

35

34

33

EXPLANATION

13–50

51–100

101–500

501–1,000

1,001–2,500

2,501–5,500

Range in number ofindependent water-qualityvalues

Number on map indicatesLevel III Ecoregion (fig. 3)

32

30

3129

35

34

Figure 9. Range of median silica concentrations for select

by ecoregion.

EXPLANATION

Range of median silicaconcentrations, in milligrams per liter

10–1516–22

23–30 (not shown)31–34

34

29

27

Number on map indicates Level III Ecoregion (fig. 3)

0 90 180 270 360 KILOMETERS

Base modified from Texas Natural ResourcesInformation System (TNRIS) digital data, 2005,1:24,000Albers equal area projection parametersCentral meridian: -100.0Standard parallel 1: 34.91666667Standard parallel 2: 27.41666667Latitude of origin: 31.16666667 

26o00'

28o00'

30o00'

32o00'

106o00' 104o00'

34o00'

36o00'

102o00' 100o00'

98o

25

25

26

26

27

27

24

30

30

31

29

23
Figure 10. Range of median calcium concentrations for selected springs in Texas, by ecoregion.

EXPLANATION

Range of median calciumconcentrations, in milligramsper liter

1–1011–5051–100

101–150151–200

33

35

29

24

34

Number on map indicatesLevel III Ecoregion (fig. 3)

0 90 180 270 360 KILOMETERS

Base modified from Texas Natural ResourcesInformation System (TNRIS) digital data, 2005,1:24,000Albers equal area projection parametersCentral meridian: -100.0Standard parallel 1: 34.91666667Standard parallel 2: 27.41666667Latitude of origin: 31.16666667 

Ecoregions from U.S. EnvironmentalProtection Agency, 2004

26o00'

28o00'

30o00'

32o00'

106o00' 104o00'

34o00'

36o00'

102o00' 100o00'

98o00' 96o00'

94o00' 25

25

26

26

27

27

24

30

30

31

29

32

32

35

34

33

23

Figure 11. Range of median magnesium concentrations foby ecoregion

EXPLANATION

Range of median magnesiumconcentrations, in milligramsper liter

2–1011–2526–50

24 51–75

29

35

34

Number on map indicatesLevel III Ecoregion (fig. 3)

0 90 180 270 360 KILOMETERS

Base modified from Texas Natural ResourcesInformation System (TNRIS) digital data, 2005,1:24,000Albers equal area projection parametersCentral meridian: -100.0Standard parallel 1: 34.91666667Standard parallel 2: 27.41666667Latitude of origin: 31.16666667 

26o00'

28o00'

30o00'

32o00'

106o00' 104o00'

34o00'

36o00'

102o00' 100o00'

9

23

25

25

26

26

27

27

24

30

30

31
Figure 12. Range of median sodium concentrations for selected springs in Texas, by ecoregion. EXPLANATION Range of median sodium concentrations, in milligrams per liter 1–10 11–50 51–100 24 101–400 273525 Number on map indicates Level III Ecoregion (fig. 3) 0 90 180 270 360 KILOMETERS Base modified from Texas Natural Resources Information System (TNRIS) digital data, 2005, 1:24,000 Albers equal area projection parameters Central meridian: -100.0 Standard parallel 1: 34.91666667 Standard parallel 2: 27.41666667 Latitude of origin: 31.16666667 Ecoregions from U.S. Environmental Protection Agency, 2004 26o00' 28o00' 30o00' 32o00' 106o00' 104o00' 34o00' 36o00' 102o00' 100o00' 98o00' 96o00' 94o00' 2525 26 26 27 24 30 30 31 29 32 32 35 34 33 23 27 Figure 13. Range of median potassium concentrations for 

by ecoregion. EXPLANATION Range of median potassium concentrations, in milligrams per liter 0.1–1 1–2 2–5 5–20 33353429 Number on map indicates Level III Ecoregion (fig. 3) 0 90 180 270 360 KILOMETERS Base modified from Texas Natural Resources Information System (TNRIS) digital data, 2005, 1:24,000 Albers equal area projection parameters Central meridian: -100.0 Standard parallel 1: 34.91666667 Standard parallel 2: 27.41666667 Latitude of origin: 31.16666667 

26o00' 28o00' 30o00' 32o00' 106o00' 104o00' 34o00' 36o00' 102o00' 100o00' 9

23 2525 26 26 2727 24 30 30 31 2
Figure 14. Range of median strontium concentrations for selected springs in Texas, by ecoregion.

EXPLANATION

Range of median strontiumconcentrations, in milligramsper liter

No values

00–1

1–4

27

29

24

33

Number on map indicatesLevel III Ecoregion (fig. 3)

0 90 180 270 360 KILOMETERS

Base modified from Texas Natural ResourcesInformation System (TNRIS) digital data, 2005,1:24,000Albers equal area projection parametersCentral meridian: -100.0Standard parallel 1: 34.91666667Standard parallel 2: 27.41666667Latitude of origin: 31.16666667 

Ecoregions from U.S. EnvironmentalProtection Agency, 2004

26o00'

28o00'

30o00'

32o00'

106o00' 104o00'

34o00'

36o00'

102o00' 100o00'

98o00' 96o00'

94o00' 25

25

26

26

27

24

30

30

31

29

32

32

35

34

33

27

23

Figure 15. Range of median bicarbonate concentrations foby ecoregion.

EXPLANATION

Range of median bicarbonateconcentrations, in milligramsper liter

10–50

51–150

151–300

301–450

34

35

29

27

Number on map indicatesLevel III Ecoregion (fig. 3)

0 90 180 270 360 KILOMETERS

Base modified from Texas Natural ResourcesInformation System (TNRIS) digital data, 2005,1:24,000Albers equal area projection parametersCentral meridian: -100.0Standard parallel 1: 34.91666667Standard parallel 2: 27.41666667Latitude of origin: 31.16666667 

26o00'

28o00'

30o00'

32o00'

106o00' 104o00'

34o00'

36o00'

102o00' 100o00'

98

25

25

26

26

27

24

30

30

31

2

27

23
Figure 16. Range of median sulfate concentrations for selected springs in Texas, by ecoregion. EXPLANATION Range of median sulfate concentrations, in milligrams per liter 2–20 21–50 51–150 151–400 34352427 Number on map indicates Level III Ecoregion (fig. 3) 0 90 180 270 360 KILOMETERS Base modified from Texas Natural Resources Information System (TNRIS) digital data, 2005, 1:24,000 Albers equal area projection parameters Central meridian: -100.0 Standard parallel 1: 34.91666667 Standard parallel 2: 27.41666667 Latitude of origin: 31.16666667 Ecoregions from U.S. Environmental Protection Agency, 2004 26o00' 28o00' 30o00' 32o00' 106o00' 104o00' 34o00' 36o00' 102o00' 100o00' 98o00' 96o00' 94o00' 2525 26 26 27 24 30 30 31 29 32 32 35 34 33 27 23 Figure 17. Range of median chloride concentrations for se

by ecoregion. EXPLANATION Range of median chloride concentrations, in milligrams per liter 2–20 21–50 51–100 101–250 33272932 Number on map indicates Level III Ecoregion (fig. 3) 0 90 180 270 360 KILOMETERS Base modified from Texas Natural Resources Information System (TNRIS) digital data, 2005, 1:24,000 Albers equal area projection parameters Central meridian: -100.0 Standard parallel 1: 34.91666667 Standard parallel 2: 27.41666667 Latitude of origin: 31.16666667 

26o00' 28o00' 30o00' 32o00' 106o00' 104o00' 34o00' 36o00' 102o00' 100o00' 98o

2525 26 26 27 24 30 30 31 29 

27 23
Figure 18. Range of median fluoride concentrations for selected springs in Texas, by ecoregion.

EXPLANATION

Range of median fluorideconcentrations, in milligramsper liter

0–0.20.2–0.50.5–1.01.0–2.0

33

27

24

29

Number on map indicatesLevel III Ecoregion (fig. 3)

0 90 180 270 360 KILOMETERS

Base modified from Texas Natural ResourcesInformation System (TNRIS) digital data, 2005,1:24,000Albers equal area projection parametersCentral meridian: -100.0Standard parallel 1: 34.91666667Standard parallel 2: 27.41666667Latitude of origin: 31.16666667 

Ecoregions from U.S. EnvironmentalProtection Agency, 2004

26o00'

28o00'

30o00'

32o00'

106o00' 104o00'

34o00'

36o00'

102o00' 100o00'

98o00' 96o00'

94o00' 25

25

26

26

27

24

30

30

31

29

32

32

35

34

33

27

23

Figure 19. Range of median nitrate nitrogen concentrationTexas, by ecoregion.

EXPLANATION

Range of median nitrateconcentrations, in milligramsper liter

25

29

27

24

0–1.0

1.0–5.0

5.0–10.0

10.0–20.0

Number on map indicatesLevel III Ecoregion (fig. 3)

0 90 180 270 360 KILOMETERS

Base modified from Texas Natural ResourcesInformation System (TNRIS) digital data, 2005,1:24,000Albers equal area projection parametersCentral meridian: -100.0Standard parallel 1: 34.91666667Standard parallel 2: 27.41666667Latitude of origin: 31.16666667 

26o00'

28o00'

30o00'

32o00'

106o00' 104o00'

34o00'

36o00'

102o00' 100o00'

98o

27

23

25

25

26

26

27

24

30

30

31

29
Figure 20. Range of median pH for selected springs in Texas, by ecoregion. EXPLANATION Range of pH Number on map indicates Level III Ecoregion (fig. 3) 0 90 180 270 360 KILOMETERS Base modified from Texas Natural Resources Information System (TNRIS) digital data, 2005, 1:24,000 Albers equal area projection parameters Central meridian: -100.0 Standard parallel 1: 34.91666667 Standard parallel 2: 27.41666667 Latitude of origin: 31.16666667 Ecoregions from U.S. Environmental Protection Agency, 2004 26o00' 28o00' 30o00' 32o00' 106o00' 104o00' 34o00' 36o00' 102o00' 100o00' 98o00' 96o00' 94o00' 2525 26 26 27 24 30 30 31 29 32 32 35 34 33 5.4–6.0 6.0–6.75 (not shown) 6.75–7.25 7.25–8.0 332924 27 23 Figure 21. Range of median dissolved solids concentratio

Texas, by ecoregion. EXPLANATION Range of median dissolved solids concentrations, in milligrams per liter 25–100 101–250 251–500 501–1,000 1,001–1,500 3135292434 Number on map indicates Level III Ecoregion (fig. 3) 0 90 180 270 360 KILOMETERS Base modified from Texas Natural Resources Information System (TNRIS) digital data, 2005, 1:24,000 Albers equal area projection parameters Central meridian: -100.0 Standard parallel 1: 34.91666667 Standard parallel 2: 27.41666667 Latitude of origin: 31.16666667 

26o00' 28o00' 30o00' 32o00' 106o00' 104o00' 34o00' 36o00' 102o00' 100o00' 98

2525 26 26 27 24 30 30 31 2

27 23
Figure 23. Range of median hardness for selected springs 

EXPLANATION

Range of median hardness,in milligrams per liter ascalcium carbonate

0–5051–200 (not shown)201–400401–550

33

34

29

Number on map indicatesLevel III Ecoregion (fig. 3)

0 90 180 270 360 KILOMETERS

Base modified from Texas Natural ResourcesInformation System (TNRIS) digital data, 2005,1:24,000Albers equal area projection parametersCentral meridian: -100.0Standard parallel 1: 34.91666667Standard parallel 2: 27.41666667Latitude of origin: 31.16666667 

26o00'

28o00'

30o00'

32o00'

106o00' 104o00'

34o00'

36o00'

102o00' 100o00'

9

25

25

26

26

27

24

30

30

31

2

27

23

Figure 22. Range of median alkalinity for selected springs in Texas, by ecoregion.

EXPLANATION

Range of median alkalinity,in milligrams per liter ascalcium carbonate

No values1–100101–250

251–400

34

24

29

33

Number on map indicatesLevel III Ecoregion (fig. 3)

0 90 180 270 360 KILOMETERS

Base modified from Texas Natural ResourcesInformation System (TNRIS) digital data, 2005,1:24,000Albers equal area projection parametersCentral meridian: -100.0Standard parallel 1: 34.91666667Standard parallel 2: 27.41666667Latitude of origin: 31.16666667 

Ecoregions from U.S. EnvironmentalProtection Agency, 2004

26o00'

28o00'

30o00'

32o00'

106o00' 104o00'

34o00'

36o00'

102o00' 100o00'

98o00' 96o00'

94o00' 25

25

26

26

27

24

30

30

31

29

32

32

35

34

33

27

23
Figure 24. Range of median specific conductance for selected springs in Texas, by ecoregion.

EXPLANATION

Range of median specificconductance, in microsiemensper centimeter at 25 degreesCelsius

No values1–250251–500501–1,0001,001–2,0002,001–3,500

31

29

24

27

33

34

Number on map indicatesLevel III Ecoregion (fig. 3)

0 90 180 270 360 KILOMETERS

Base modified from Texas Natural ResourcesInformation System (TNRIS) digital data, 2005,1:24,000Albers equal area projection parametersCentral meridian: -100.0Standard parallel 1: 34.91666667Standard parallel 2: 27.41666667Latitude of origin: 31.16666667 

Ecoregions from U.S. EnvironmentalProtection Agency, 2004

26o00'

28o00'

30o00'

32o00'

106o00' 104o00'

34o00'

36o00'

102o00' 100o00'

98o00' 96o00'

94o00' 25

25

26

26

27

24

30

30

31

29

32

32

35

34

33

27

23

Figure 25. Range of median temperature for selected spri

0 90 180 270 360 KILOMETERS

Base modified from Texas Natural ResourcesInformation System (TNRIS) digital data, 2005,1:24,000Albers equal area projection parametersCentral meridian: -100.0Standard parallel 1: 34.91666667Standard parallel 2: 27.41666667Latitude of origin: 31.16666667 

26o00'

28o00'

30o00'

32o00'

106o00' 104o00'

34o00'

36o00'

102o00' 100o00'

9

EXPLANATION

Range of median temperature,in degrees Celsius

Number on map indicatesLevel III Ecoregion (fig. 3)

No values17–1819–2021–2223–25

34

27

29

26

24

25

25

26

26

27

24

30

30

31

2

27

23
Historical Water-Quality Data for Selected Springs, by Ecoregion 21

High Plains

The High Plains (Ecoregion 25) is represented by only six 

springs in the water-quality database because of the small number of springs for this ecoregion in the database. In Texas, the 

High Plains is noted more for recharge to the Ogallala aquifer 

than discharge to springs within the boundaries of the ecoregion, although springs associated with the Ogallala aquifer are 

abundant at the Caprock escarpment in adjacent Ecoregion 26 

(fig. 3). Only two of the six springs are well within the boundaries of the High Plains ecoregion; the remaining four springs 

are at the Caprock escarpment. The few water-quality data for 

springs in the High Plains indicate that spring flow contains low 

to moderate concentrations of selected constituents; however, 

median pH (8.0) is the highest of any spring in level III ecoregions in Texas. The few data available from the small number 

of sizeable springs in the High Plains and variability of the data 

likely do not provide a reliable evaluation of water quality in the 

ecoregion. A variety of small springs and seeps, many at playa 

lakes, in the High Plains are listed in Brune (1981).

Southwestern Tablelands

The Southwestern Tablelands (Ecoregion 26) is represented by 29 springs in the water-quality database. This comparatively large number of springs is attributed to the high spatial density (table 1) of springs along the Caprock escarpment. 

Many of the springs in the Southwestern Tablelands of Texas 

flow from the Blaine aquifer and commonly are noted for producing saline water. Other selected springs that flow from the 

Ogallala aquifer along the Caprock escarpment and from the 

Seymour aquifer commonly report high salinity and nitrate 

(nitrogen) concentrations (Ashworth and Hopkins, 1995). 

Selected springs in the Southwestern Tablelands have the highest or second highest median concentrations of silica (32 milligrams per liter) and nitrate (20 milligrams per liter) of all 

springs in Texas level III ecoregions. 

Central Great Plains

The Central Great Plains (Ecoregion 27) is represented by 

15 springs in the water-quality database. Many of the springs 

selected for Ecoregion 27 flow from the Ogallala aquifer; others 

flow from the Seymour aquifer. Springs discharging from the 

Ogallala aquifer are reported to have high concentrations of calcium and hard waters (Brune, 1981), and parts of the Seymour 

aquifer have been reported to have high nitrate concentrations 

(Ashworth and Hopkins, 1995). Median concentrations of silica 

(34 milligrams per liter), magnesium (35 milligrams per liter), 

sulfate (112 milligrams per liter), nitrate (12 milligrams per 

liter), and dissolved solids (670 milligrams per liter) in selected 

springs of the Central Great Plains are the highest or second 

highest of any spring in level III ecoregions. Problems associated with springs contributing high concentrations of selected 

constituents to surface-water bodies in the ecoregion is a watermanagement issue (Ward, 1963). Conversely, the habitats of 

some inland fish species depend on the maintenance of these 

same high concentrations (Hubbs and others, 1991).

Cross Timbers

The Cross Timbers (Ecoregion 29) is represented by 14 

springs in the water-quality database. Most of the selected 

springs in Ecoregion 29 are along the southern boundary with 

Ecoregions 30 (Edwards Plateau) and 32 (Texas Blackland 

Prairies) (fig. 3). Springs selected in the southern part of the 

Cross Timbers flow from aquifers normally associated with the 

Edwards Plateau and Blackland Prairie, including the Edwards 

(Balcones fault zone), Ellenburger-San Saba, Marble Falls, and 

Trinity aquifers. Spring flow from the Ellenburger-San Saba 

and Marble Falls aquifers can be highly mineralized within 

short distances of recharge zones (Ashworth and Hopkins, 

1995); springs of the Edwards and Trinity aquifers often are 

hard, alkaline, and have high bicarbonate concentrations. 

Selected springs in the Cross Timbers have the highest, or second or third highest, median concentrations of calcium (110 

milligrams per liter), magnesium (34 milligrams per liter), 

sodium (83 milligrams per liter), potassium (4.6 milligrams per 

liter), bicarbonate (410 milligrams per liter), chloride (141 milligrams per liter), dissolved solids (616 milligrams per liter), 

alkalinity as calcium carbonate (368 milligrams per liter), hardness as calcium carbonate (408 milligrams per liter), and specific conductance (1,090 microsiemens per centimeter at 25 

degrees Celsius) among springs of all level III ecoregions. The 

highly variable values are attributed to the difference between 

the water quality of springs (associated with the Edwards Plateau) in the southern part of the ecoregion and springs in the 

northern part of the ecoregion. San Saba Springs is represented 

by 27 sampling visits, greatly influencing summary statistics. 

Spring flow in the Cross Timbers contributes to base flow of the 

Trinity, Brazos, and Colorado Rivers.

Edwards Plateau

The Edwards Plateau (Ecoregion 30) is represented by 88 

springs in the water-quality database. This large number is 

attributed to the high spatial density (table 1) of springs in the 

ecoregion. Selected springs of the Edwards Plateau issue from 

the Edwards (Balcones fault zone), Edwards-Trinity (Plateau), 

Trinity, Ellenburger-San Saba, and Marble Falls aquifers. 

These carbonate aquifers are associated with hard water and 

high concentrations of calcium and bicarbonate (Ashworth and 

Hopkins, 1995). Selected springs in the Edwards Plateau have 

the second, third, or fourth highest median concentrations of 

calcium (90 milligrams per liter), bicarbonate (323 milligrams 

per liter), nitrate (8.1 milligrams per liter), and alkalinity as calcium carbonate (270 milligrams per liter) of all springs in level 

III ecoregions. Hueco Springs is represented by 92 sampling 

visits, greatly influencing summary statistics. Spring flow in the 

ecoregion constitutes the base flow of numerous Texas rivers, 

including the Colorado, Guadalupe, San Antonio, and Nueces 

Rivers.
22 Compilation of Historical Water-Quality Data for Selected Springs in Texas, by Ecoregion

Southern Texas Plains

The Southern Texas Plains (Ecoregion 31) is represented 

by seven springs in the water-quality database. The small number is attributed to the semiarid climate and flat topography of 

the ecoregion. Most of the springs selected in the Southern 

Texas Plains are located along the northern boundary with 

Ecoregion 30 (Edwards Plateau) (fig. 3) and are associated with 

the Edwards (Balcones fault zone) and Edwards-Trinity (Plateau) aquifers. Springs are sparse throughout most of the ecoregion; Carrizo Springs is the only spring not associated with the 

Edwards or Edwards-Trinity aquifers. Selected springs in the 

Southern Texas Plains have the second, third, or fourth lowest 

median concentrations of magnesium (7 milligrams per liter), 

sodium (6 milligrams per liter), potassium (0.9 milligram per 

liter), sulfate (7 milligrams per liter), chloride (10 milligrams 

per liter), and dissolved solids (245 milligrams per liter) of all 

springs in level III ecoregions. The largest springs in the ecoregion, San Felipe, Las Moras, and Leona Springs, are represented by 55 sampling visits, greatly influencing summary statistics. Spring flow in the ecoregion contributes to the base flow 

of the Rio Grande and the Nueces River.

Texas Blackland Prairies

The Texas Blackland Prairies (Ecoregion 32) is represented by 11 springs in the water-quality database. Similar to 

Ecoregion 31 (Southern Texas Plains), selected springs of the 

Texas Blackland Prairies are along the boundary with Ecoregion 30 (Edwards Plateau) and are associated with the Edwards 

(Balcones fault zone) aquifer. Many of the largest springs in 

Texas are along the Balcones escarpment separating Ecoregions 

30 and 32 (fig. 3), including Comal, San Marcos, Barton, and 

San Antonio Springs. Selected springs in the Texas Blackland 

Prairies have median concentrations of selected constituents 

mostly in the mid-range of median concentrations from selected 

springs of other level III ecoregions, although the median strontium concentration is the second highest (0.7 milligram per 

liter). Selected springs in Ecoregion 32 have the most waterquality measurements of springs in any Texas ecoregion (5,387 

individual measurements). The preferential sampling of Barton, 

Comal, Old Mill, and San Marcos Springs greatly influences 

summary statistics. Spring flow in the ecoregion contributes a 

large part of the base flow to numerous Texas rivers, including 

the Colorado, Guadalupe, and San Antonio Rivers.

East Central Texas Plains

The East Central Texas Plains (Ecoregion 33) is represented by 15 springs in the water-quality database. Selected 

springs in the East Central Texas Plains are associated with 

(roughly from southwest to northeast) the Carrizo-Wilcox, 

Queen City, Sparta, and Yegua Jackson aquifers. Median concentrations of calcium (14 milligrams per liter), magnesium 

(2 milligrams per liter), bicarbonate (44 milligrams per liter), 

fluoride (0.1 milligram per liter), alkalinity as calcium carbonate (79 milligrams per liter), hardness as calcium carbonate (44 

milligrams per liter), and specific conductance (138 microsiemens per centimeter at 25 degrees Celsius) were the lowest or 

second lowest of all springs in level III ecoregions. Median pH 

(5.4) shows spring flow to be somewhat acidic.

Western Gulf Coastal Plain

The Western Gulf Coastal Plain (Ecoregion 34) is represented by three springs in the water-quality database, each 

spring separated by a considerable distance. The small number 

is attributed to the flat topography of the ecoregion. The three 

selected springs have very little flow and issue from the Gulf 

Coast aquifer. The few water-quality data for the selected 

springs indicate that median concentrations of sodium (97 milligrams per liter), potassium (12 milligrams per liter), and chloride (244 milligrams per liter) are the second highest of all 

springs in level III ecoregions.

South Central Plains

The South Central Plains (Ecoregion 35) is represented by 

14 springs in the water-quality database. Selected springs in the 

South Central Plains are associated with (roughly from southwest to northeast) the Carrizo-Wilcox, Queen City, Sparta, 

Yegua Jackson, and Gulf Coast aquifers. Median concentrations of calcium (1 milligram per liter), magnesium (2 milligrams per liter), sodium (4 milligrams per liter), bicarbonate 

(12 milligrams per liter), sulfate (2 milligrams per liter), chloride (6 milligrams per liter), nitrate (1.5 milligrams per liter), 

dissolved solids (25 milligrams per liter), hardness as calcium 

carbonate (10 milligrams per liter), and specific conductance 

(34 microsiemens per centimeter at 25 degrees Celsius) were 

the lowest or second lowest of all springs in level III ecoregions. 

Median pH (5.6) shows spring flow to be slightly acidic

Summary

A digital database of spring locations and spring-flow 

measurements in Texas has been recently compiled. Following 

the publication of this database, a series of stakeholder meetings 

were held regarding springs in Texas. A need was identified to 

aggregate water-quality data for a wide variety of Texas springs 

into a digital database. To address this need, the published database of spring locations and spring-flow measurements was 

updated, and springs were ranked by mean spring flow for each 

level III ecoregion in Texas. Springs with the highest mean 

spring flow in each ecoregion were selected for inclusion in the 

water-quality database. Additionally, the selection of springs 

for historical water-quality and spring-flow data entry and 

analysis was facilitated by a survey mailed to stakeholders 

across Texas. In total, 232 springs were selected for inclusion in 

the water-quality database. The springs represent all level III 
References 23

ecoregions in Texas, a large percentage of aquifers, and most of 

the river basins in the State. A brief assessment of the waterquality data for springs in Texas shows that very few data are 

available in Ecoregions 23 (Arizona/New Mexico Mountains), 

25 (High Plains), 33 (East Central Texas Plains), 34 (Western 

Gulf Coastal Plain), and 35 (South Central Plains). More waterquality data are available for Ecoregions 24 (Chihuahuan 

Deserts), 30 (Edwards Plateau), and 32 (Texas Blackland Prairies). In general, selected constituent concentrations in Texas 

springs, including silica, calcium, magnesium, sodium, potassium, strontium, sulfate, chloride, fluoride, nitrate, dissolved 

solids, and hardness as calcium carbonate, are comparatively 

high in Ecoregions 24 (Chihuahuan Deserts), 26 (Southwestern 

Tablelands), 27 (Central Great Plains), and 29 (Cross Timbers), 

mostly as a result of subsurface geology. In general, comparatively low concentrations of selected constituents in Texas 

springs are associated with Ecoregions 23 (Arizona/New Mexico Mountains), 31 (Southern Texas Plains), 33 (East Central 

Texas Plains), and 35 (South Central Plains), closely resembling the water quality of major and minor aquifers in those 

areas. To more comprehensively assess water quality of springs 

in Texas, additional data collection and monitoring are needed 

statewide.

References

Aragon Long, S.C., Reece, B.D., and Eames, D.R., 2005, Water 

resources data, Texas, water year 2004—Volumes 1–5: U.S. 

Geological Survey Water-Data Reports TX–04–1, TX–04–2, 

TX–04–3, TX–04–4, TX–04–5, accessed October 2005, at 

http://pubs.usgs.gov/wdr/2004/WDR-TX-04-1/. 

Ashworth, J.B., and Hopkins, J., 1995, Major and minor aquifers of Texas: Texas Water Development Board Report 345, 

69 p.

Baker, E.T., Jr., 2005, Bibliography of ground-water references 

for all 254 counties in Texas, 1886-2001: U.S. Geological 

Survey Open-File Report 2005–1270, 321 p., accessed 

January 2006, at http://pubs.usgs.gov/of/2005/1270/. 

Bonacci, O., 1995, Ground water behaviour in karst—Example 

of the Ombla Spring (Croatia): Journal of Hydrology, v. 165, 

p. 113–134.

Brannan, D.K., Brannan, C.R., and Lee, T.E., 2003, Reproductive and territorial behavior of Comanche Springs 

pupfish (Cyprinodon elegans) in San Solomon Spring pool, 

Balmorhea State Park, Reeves County, Texas: Southwestern 

Naturalist, v. 48, p. 85–88.

Brune, Gunnar, 1975, Major and historical springs of Texas: 

Texas Water Development Board Report 189, 95 p.

Brune, Gunnar, 1981, Springs of Texas, volume 1: Fort Worth, 

Tex., Branch-Smith, Inc., 566 p.

Cartwright, I., Weaver, T., Tweed, S., Ahearne, D., Cooper, M., 

Czapnik, K., and Tranter, J., 2002, Stable isotope geochemistry of cold CO2-bearing mineral spring waters, Daylesford, 

Victoria, Australia—Sources of gas and water and links with 

waning volcanism: Chemical Geology, v. 185, p. 71–91.

Grasby, S.E., Hutcheon, I., and Krouse, H.R., 2000, The influence of water-rock interaction on the chemistry of thermal 

springs in western Canada: Applied Geochemistry, v. 15, 

p. 439–454.

Griffith, G.E., Bryce, S.A., Omernik, J.M., Comstock, J.A., 

Rogers, A.C., Harrison, B., Hatch, S.L., and Bezanson, D., 

2004, Ecoregions of Texas (color poster with map, descriptive text, and photographs): Reston, Va., U.S. Geological 

Survey, scale 1:2,500,000.

Heitmuller, F.T., and Reece, B.D., 2003, Database of historically documented springs and spring flow measurements in 

Texas: U.S. Geological Survey Open-File Report 03–315, 

4 p., database on CD-ROM.

Hubbs, C., 2001, Environmental correlates to the abundance of 

spring-adapted versus stream-adapted fishes: Texas Journal 

of Science, v. 53, p. 299–326.

Hubbs, C., Edwards, R.J., and Garrett, G.P., 1991, An annotated 

checklist of the fresh-water fishes of Texas, with keys to 

identification of species: Texas Journal of Science, v. 43, 

p. 1–56.

Shiner, J.L., 1983, Large springs and early American Indians: 

Plains Anthropologist, v. 28, p. 1–7.

Texas Water Development Board, 1990, Maps—Major aquifers 

and minor aquifers: accessed March 2006, at 

http:// www.twdb.state.tx.us/mapping/index.asp

Texas Water Development Board, 2002, Major Texas rivers: 

accessed March 2006, at http:// www.twdb.state.tx.us/

mapping/maps/pdf/mtr_34X34.pdf

Texas Water Development Board, 2005, Water Information 

Integration and Dissemination: accessed October 2005, at 

http://wiid.twdb.state.tx.us/. 

Uliana, M.M., and Sharp, J.M., 2001, Tracing regional flow 

paths to major springs in Trans-Pecos Texas using geochemical data and geochemical models: Chemical Geology, 

v. 179, p. 53–72.

U.S. Environmental Protection Agency, 2004, Level III and IV 

ecoregions of Texas: Digital data accessed July 2005, at 

http://ftp.epa.gov/wed/ecoregions/tx/.

U.S. Geological Survey, 2001, USGS water data for the 

Nation—Surface water: National Water Information System 

(NWISWeb) at http://waterdata.usgs.gov/nwis/.

Ward, P.E., 1963, Geology and ground-water features of salt 

springs, seeps, and plains in the Arkansas and Red River 

Basins of western Oklahoma and adjacent parts of Kansas 

and Texas: U.S. Geological Survey Open-File Report 63–

132, 71 p., 3 pls.

William F. Guyton & Associates, 1979, Geohydrology of 

Comal, San Marcos, and Hueco Springs: Texas Water Development Board Report 234, 85 p.
24 Regional Assessment of Historical Water Quality and Spring Flow for Selected Springs in Texas 

Table 4

Table 4. Texas springs selected for water-quality and spring-flow database—Continued. 

Station number Spring County Level III ecoregion River basin

08407600 Smith Spring Culberson 23 Rio Grande

1

08425500 Phantom Lake Spring Jeff Davis 24 Rio Grande

2

08427000 Giffin Springs Reeves 24 Rio Grande

1

08427500 San Solomon Springs Reeves 24 Rio Grande

08429000 West Sandia Spring Reeves 24 Rio Grande

08430000 East Sandia Spring Reeves 24 Rio Grande

08444500 Comanche Springs Pecos 24 Rio Grande

08448500 Goodenough Springs Val Verde 24 Rio Grande

08451300 Cantu Spring Val Verde 24 Rio Grande

291053102593401 Hot Springs Brewster 24 Rio Grande

291056102571401 Rio Grande Village Spring no. 4 Brewster 24 Rio Grande

291057102571101 Rio Grande Village Spring no. 1 Brewster 24 Rio Grande

292335101011501 McKee Springs Val Verde 24 Rio Grande

294731101213101 Dead Man Springs Val Verde 24 Rio Grande

300220104355801 Chinati Hot Spring no. 1 Presidio 24 Rio Grande

300223104355401 Chinati Hot Spring no. 2 Presidio 24 Rio Grande

300231101323101 Cox Springs Val Verde 24 Rio Grande

300725101320001 3YR–54–60–302 Val Verde 24 Rio Grande

300826101325801 Howard Springs Val Verde 24 Rio Grande

301731101463101 Sweetwater Springs Terrell 24 Rio Grande

301831101463101 Geddis Springs Terrell 24 Rio Grande

302259101424001 Richland Springs Terrell 24 Rio Grande

302300101420001 Wolf Spring Terrell 24 Rio Grande

302811101481401 T–5 Springs Terrell 24 Rio Grande

302943101405901 3HJ–54–35–203 Crockett 24 Rio Grande

305331103013201 Leon Springs Pecos 24 Rio Grande

305831102493201 San Pedro Springs Pecos 24 Rio Grande

305851103453301 Saragosa Spring Reeves 24 Rio Grande

310002102551101 Diamond Y Springs Pecos 24 Rio Grande

311606102573201 Santa Rosa Spring Pecos 24 Rio Grande

324430102183201 Balch Springs Gaines 25 Colorado

333230101423201 Buffalo Springs Lubbock 25 Brazos

342221101125501 3BL–11–47–102 Briscoe 25 Red

344330101224401 3BL–11–21–308 Briscoe 25 Red

344358101235101 3BL–11–21–302 Briscoe 25 Red

362930102473201 Buffalo Springs Dallam 25 Canadian

07307700 Roaring Springs Motley 26 Red

324530100423101 Camp Springs Scurry 26 Brazos

333600100130101 Spring no. 1 King 26 Red

333700100110101 Spring no. 4 King 26 Red

333930101073201 Couch Springs Crosby 26 Brazos

335700100090102 Salt Springs Cottle 26 Red

335800100070101 Spring no. 5 Cottle 26 Red

341333101115201 3JW–11–55–204 Floyd 26 Red

342007101120101 3BL–11–47–201 Briscoe 26 Red

343205101250801 3BL–11–29–801 Briscoe 26 Red

343251100252201 Estelline Salt Springs Hall 26 Red

Table 4. Texas springs selected for water-quality and spring-flow database.
Table 4 25

344357101225001 3BL–11–21–306 Briscoe 26 Red

344409101223901 3BL–11–21–305 Briscoe 26 Red

344430101233201 Hulsey Springs Briscoe 26 Red

344847100471001 Bitter Creek Springs Donley 26 Red

345034100204801 Roscoe Springs Collingsworth 26 Red

345225100231901 O’Hair Springs Collingsworth 26 Red

350210100234801 3DU–56–19–903 Collingsworth 26 Red

350213100083001 3DU–56–39–903 Collingsworth 26 Red

350222100550701 3JA–55–78–801 Donley 26 Red

350330100083201 Wolf Springs Collingsworth 26 Red

350551100104501 3DU–56–32–208 Collingsworth 26 Red

350727100085801 3DU–56–33–307 Collingsworth 26 Red

350749100174801 Elm Creek Springs Collingsworth 26 Red

350844100320701 3DU–55–29–905 Collingsworth 26 Red

350900100140101 3DU–55–57–702 Collingsworth 26 Red

351048100025401 3DU–55–65–502 Collingsworth 26 Red

351130100113101 Lehman Springs Wheeler 26 Red

353243100282901 Fort Elliot Springs Wheeler 26 Red

313132100121701 Indian Springs Tom Green 27 Colorado

315302099421401 Pecan Spring Coleman 27 Colorado

332933099460901 3RS–21–34–323 Knox 27 Brazos

333330098083101 Buffalo Springs Clay 27 Red

340530098570501 China Springs Wichita 27 Red

345055100035601 Sand Springs Collingsworth 27 Red

345307100213201 3DU–12–06–704 Collingsworth 27 Red

345544100145201 3DU–12–07–405 Collingsworth 27 Red

345835100434401 3JA–12–03–109 Donley 27 Red

345853100442701 3JA–12–03–103 Donley 27 Red

345916100471001 3JA–12–02–303 Donley 27 Red

345918100204601 Wischkaemper Springs Collingsworth 27 Red

345920100473001 3JA–12–02–304 Donley 27 Red

352430100061101 Wheeler Springs Wheeler 27 Red

353230100073101 Rathjen Springs Wheeler 27 Red

08103500 Hannah Springs Lampasas 29 Brazos

081465001 San Saba Springs San Saba 29 Colorado

304313097441101 Cowan Creek Spring Williamson 29 Brazos

305250097395401 3AX–58–03–911 Bell 29 Brazos

305317097392401 3AX–58–03–909 Bell 29 Brazos

305331097403101 Warwick Springs Bell 29 Brazos

310031097293101 Childers Springs Bell 29 Brazos

310320098110001 Hancock Springs Lampasas 29 Brazos

310331098113101 Swimming Pool Springs Lampasas 29 Brazos

311213098543901 Baker Spring San Saba 29 Colorado

311632098564401 Richland Springs San Saba 29 Colorado

311706099003101 Hall Springs San Saba 29 Colorado

314731097463101 Pierson Spring Bosque 29 Brazos

321119097342601 3PX–32–52–503 Johnson 29 Brazos

08127200 Anson Springs Tom Green 30 Colorado

Table 4. Texas springs selected for water-quality and spring-flow database—Continued. 

Station number Spring County Level III ecoregion River basin
26 Regional Assessment of Historical Water Quality and Spring Flow for Selected Springs in Texas 

08129000 Spring Creek Springs Irion 30 Colorado

108129500 Dove Creek Springs Irion 30 Colorado

1

08143900 Springs at Fort McKavett Menard 30 Colorado

1

08149395 Tanner Springs Edwards 30 Colorado

108149500 Seven Hundred Springs Edwards 30 Colorado

08165700 Welch Springs Kerr 30 Guadalupe

08165710 Fessenden Springs Kerr 30 Guadalupe

2

08168000 Hueco Springs Comal 30 Guadalupe

2

08170990 Jacob’s Well Spring Hays 30 Guadalupe

08179700 Nisbet Springs Medina 30 San Antonio

293031098543101 Diversion Dam Springs Medina 30 San Antonio

293331099573101 Spring Creek Spring Uvalde 30 Nueces

293331100153101 Schwander Springs Kinney 30 Nueces

293331100163101 Silver Springs Kinney 30 Nueces

294031100563101 Slaughter Bend Springs Val Verde 30 Rio Grande

294103098571101 Wonder Hole Bandera 30 San Antonio

294131100013101 Camp Wood Spring Real 30 Nueces

294159098583201 Cold Springs Bandera 30 San Antonio

294231099463101 Spring Branch Springs Real 30 Nueces

294308101012901 Gillis Springs Val Verde 30 Rio Grande

294501100240101 Kickapoo Springs Edwards 30 Nueces

294731100113101 Paint Bluff Springs Edwards 30 Nueces

294831100103101 Roberts Springs Edwards 30 Nueces

295108098292901 Honey Creek Spring Comal 30 Guadalupe

295131100083101 Pulliam Springs Edwards 30 Nueces

295146099483701 Big Springs Real 30 Nueces

295329100593201 3YR–70–01–703 Val Verde 30 Rio Grande

295332100593301 3YR–70–01–704 Val Verde 30 Rio Grande

295338098260101 4A–16 Comal Comal 30 Guadalupe

295348100585901 Dolan Springs Val Verde 30 Rio Grande

295410100003001 McCurdy Springs Edwards 30 Nueces

295415097550601 Seep Springs Hays 30 Guadalupe

295431098153101 Cranes Mill Springs Comal 30 Guadalupe

295431098193101 Wolfe Springs Comal 30 Guadalupe

295431101003101 Finegan Springs Val Verde 30 Rio Grande

295437098263501 Spring Branch Springs Comal 30 Guadalupe

295531098183101 Bishop Spring Comal 30 Guadalupe

295731099453101 Chittim Springs Real 30 Nueces

295731099573101 Morriss Spring Real 30 Nueces

295852099264001 Lynx Haven Springs Kerr 30 Guadalupe

295901098005001 Fern Bank Springs Hays 30 Guadalupe

300031099223101 Mystic Springs Kerr 30 Guadalupe

300113101111101 Hudspeth Springs Val Verde 30 Rio Grande

300127100040601 Hackberry Springs Edwards 30 Nueces

300231099003101 Cypress Springs Kerr 30 Guadalupe

300331099183101 Kelly Springs Kerr 30 Guadalupe

300331101103101 Pecan Springs Val Verde 30 Rio Grande

300435099342201 Fish and Wildlife Springs Kerr 30 Guadalupe

Table 4. Texas springs selected for water-quality and spring-flow database—Continued. 

Station number Spring County Level III ecoregion River basin
Table 4 27

300631099123101 Goat Springs Kerr 30 Guadalupe

300631099153101 Henderson Springs Kerr 30 Guadalupe

300931101073101 Juno Springs Val Verde 30 Rio Grande

301002099203401 Ellebracht Springs Kerr 30 Guadalupe

301031099173101 Fall Springs Gillespie 30 Guadalupe

301531098043101 Barton Creek Springs Hays 30 Colorado

301619099523801 Big Paint Springs Edwards 30 Colorado

301649097464901 Deep Eddy Spring Travis 30 Colorado

301702099133301 3KK–56–47–701 Gillespie 30 Colorado

301738097470701 Power House Spring Travis 30 Colorado

301836099381001 Water Hole Spring Kimble 30 Colorado

301903099550501 Christmas Canyon Spring Kimble 30 Colorado

301919099550701 Junior Canyon Spring Kimble 30 Colorado

302036098072801 Hamilton Springs Travis 30 Colorado

301921098225001 Crofts Spring Blanco 30 Colorado

302249099550701 Coleman Springs Kimble 30 Colorado

302848098084301 Krause Springs Burnet 30 Colorado

303825099551401 3RK–56–17–801 Kimble 30 Colorado

304002097450201 Knight Springs Williamson 30 Brazos

304231099193101 Kothmann Springs Mason 30 Colorado

304531101413101 Live Oak Spring Crockett 30 Rio Grande

305528098283001 Boiling Springs San Saba 30 Colorado

305631099533101 Wilkinson Springs Menard 30 Colorado

305849098462401 Heck Springs San Saba 30 Colorado

310043099160501 Indian Mound Springs McCulloch 30 Colorado

310224099161101 Hudson-Pipe Springs McCulloch 30 Colorado

310309098291001 Gorman Springs San Saba 30 Colorado

310514098273001 Sulphur Spring San Saba 30 Colorado

310618098593801 Deep Creek Spring San Saba 30 Colorado

310625098502201 Wallace Springs San Saba 30 Colorado

310812098554201 Fleming Springs San Saba 30 Colorado

310914098550401 Sloan Springs San Saba 30 Colorado

310927100074601 Kickapoo Spring Tom Green 30 Colorado

311028098403801 Crystal Springs San Saba 30 Colorado

311048098544601 Hart Spring San Saba 30 Colorado

311101098560101 Flemming Spring San Saba 30 Colorado

311131100303101 Mill Spring Tom Green 30 Colorado

311248098594401 Springs on Maxwell Ranch San Saba 30 Colorado

311506100150401 Lipan Spring Tom Green 30 Colorado

08204000 Leona Springs Uvalde 31 Nueces

08452800 San Felipe Springs Val Verde 31 Rio Grande

08454800 Mud Springs Kinney 31 Rio Grande

08454890 Pinto Springs Kinney 31 Rio Grande

208456300 Las Moras Springs Kinney 31 Rio Grande

283031099523101 Carrizo Springs Dimmit 31 Nueces

291031099543101 Soldiers Camp Springs Uvalde 31 Nueces

08104300 Salado Springs Bell 32 Brazos

2

08155500 Barton Springs Travis 32 Colorado

Table 4. Texas springs selected for water-quality and spring-flow database—Continued. 

Station number Spring County Level III ecoregion River basin
28 Regional Assessment of Historical Water Quality and Spring Flow for Selected Springs in Texas 

1 Active partial-record USGS station.

2 Active continuous USGS station.

3 Name derived from Texas state well number.

4 Name from reports of Texas Board of Water Engineers or Texas Water Development Board.

108155503 Old Mill Springs Travis 32 Colorado

208168710 Comal Springs Comal 32 Guadalupe

2

08170000 San Marcos Springs Hays 32 Guadalupe

1

08177818 San Antonio Springs Bexar 32 San Antonio

108178090 San Pedro Springs Bexar 32 San Antonio

291631098293101 Mitchell Lake Spring Bexar 32 San Antonio

292731098103101 Martinez Springs Bexar 32 San Antonio

304113097390101 Berry Springs Williamson 32 Brazos

324630096473101 Browder Springs Dallas 32 Trinity

291657098020801 Sutherland Springs Wilson 33 San Antonio

293527097353101 Sour Springs Gonzales 33 Guadalupe

294402097354700 Soda Springs Caldwell 33 Guadalupe

302030097210601 3AT–58–46–106 Bastrop 33 Colorado

302128097061701 3RZ–58–48–103 Lee 33 Brazos

302431097153101 Lawhon Springs Lee 33 Brazos

303324096461001 3BS–59–26–608 Burleson 33 Brazos

303407096454701 Spring Lake Springs Burleson 33 Brazos

303601096412601 3BS–59–27–209 Burleson 33 Brazos

303700096381301 Pettis Spring Burleson 33 Brazos

303737096003200 Kellum Springs Grimes 33 Brazos

321735095543001 3LT–34–41–603 Henderson 33 Trinity

322117095545601 Roher Springs Henderson 33 Trinity

323030095533101 Riley Spring Van Zandt 33 Trinity

330830095373101 Sulphur Springs Hopkins 33 Sulphur

263513098105001 Santa Anita Seeps Hidalgo 34 Nueces-Rio Grande

283456096351801 San Luis Springs Calhoun 34 Lavaca-Guadalupe

293431094243101 Smith Springs Galveston 34 Neches-Trinity

302904094504501 3SB–61–34–107 Liberty 35 Trinity

302906094504101 3SB–61–34–108 Liberty 35 Trinity

303514095070701 Harris Springs San Jacinto 35 Trinity

305929093592101 Buck Spring Jasper 35 Neches

310333094162501 Boykin Spring Jasper 35 Neches

312731095303101 Caney Creek Springs Houston 35 Trinity

312731095323101 Hays Branch Springs Houston 35 Trinity

313331095313101 Elkhart Creek Springs Houston 35 Trinity

314948094363101 Tonkawa Springs Nacogdoches 35 Neches

315343094465301 Sulphur Springs Rusk 35 Neches

323531094033101 Coushatta Spring Harrison 35 Cypress

323932095224501 Dumas Spring Wood 35 Sabine

324030095241201 Peacock Spring Wood 35 Sabine

334530094533101 Bryarly Springs Red River 35 Red

Table 4. Texas springs selected for water-quality and spring-flow database—Continued. 

Station number Spring County Level III ecoregion River basin
Table 6 29

Table 6

Table 5

Table 5. Number of values used to compute mean, median, and standard deviation of selected water-quality constituents and 

properties for selected springs in Texas, by ecoregion.

[--, no values]

Table 6. Water-quality parameter codes and description of selected constituents and properties used in statistical summaries and 

maps for selected springs in Texas.

1 Sodium summary statistics and maps applied to all values for both parameter codes.

2 Strontium converted from micrograms per liter to milligrams per liter for analysis.

Level III

ecoregion

ID

Silica Calcium

Magnesium

SodiumPotassiumStrontium

Bicarbonate

SulfateChlorideFluoride

Nitrate

nitrogen

pH

Dissolved

solids

AlkalinityHardness

Specific

conductance

Temperature

Total

23 1 1 1 1 1 -- 1 1 1 1 1 1 1 -- 1 -- -- 13

24 115 123 123 119 69 35 156 168 174 67 111 91 150 129 166 159 142 2,097

25 1 4 4 4 1 -- 4 5 5 1 1 1 4 -- 4 -- 2 41

26 22 21 23 24 12 2 25 30 31 16 23 22 24 10 22 19 15 341

27 9 14 14 14 2 -- 18 15 16 11 11 14 12 8 14 11 11 194

29 21 31 31 31 15 3 33 33 33 22 29 25 32 18 32 34 35 458

30 121 126 124 131 75 33 166 181 195 90 137 109 177 119 199 148 175 2,306

31 32 39 39 39 25 18 40 42 42 29 37 32 41 34 40 33 27 589

32 469 84 84 98 49 310 183 559 557 65 79 440 485 212 545 625 543 5,387

33 5 9 9 9 3 2 12 13 13 4 5 5 11 6 11 5 6 128

34 2 3 3 3 1 -- 3 4 4 1 2 1 4 -- 3 -- -- 34

35 3 5 5 5 1 -- 9 8 9 4 6 6 7 -- 7 6 6 87

TOTAL 801 460 460 478 254 403 650 1,059 1,080 311 442 747 948 536 1,044 1,040 962 11,675

Constituent

or property

U.S. Geological

Survey

parameter

code

Description

Silica 00955 Silica, water, filtered, milligrams per liter

Calcium 00910 Calcium, water, unfiltered, milligrams per liter as calcium carbonate

Magnesium 00920 Magnesium, water, unfiltered, milligrams per liter as calcium carbonate

Sodium1 00929 Sodium, water, unfiltered, recoverable, milligrams per liter

00933 Sodium plus potassium, water, filtered, milligrams per liter as sodium

Potassium 00937 Potassium, water, unfiltered, recoverable, milligrams per liter

Strontium 01080 Strontium, water, filtered, micrograms per liter2

Bicarbonate 00440 Bicarbonate, water, unfiltered, fixed endpoint (pH 4.5) titration, field, milligrams per liter

Sulfate 00945 Sulfate, water, filtered, milligrams per liter

Chloride 00940 Chloride, water, filtered, milligrams per liter

Fluoride 00951 Fluoride, water, unfiltered, milligrams per liter

Nitrate nitrogen 71850 Nitrate nitrogen, water, unfiltered, milligrams per liter

pH 00403 pH, water, unfiltered, laboratory, standard units

Dissolved solids 70301 Residue, water, filtered, sum of constituents, milligrams per liter

Alkalinity 00410 Acid neutralizing capacity, water, unfiltered, fixed endpoint (pH 4.5) titration, field, milligrams per 

liter as calcium carbonate

Hardness 00900 Hardness, water, milligrams per liter as calcium carbonate

Specific conductance 00095 Specific conductance, water, unfiltered, microsiemens per centimeter at 25 degrees Celsius

Temperature 00010 Temperature, water, degrees Celsius
30 Regional Assessment of Historical Water Quality and Spring Flow for Selected Springs in Texas 

Table 7

Table 7. Mean, median, and standard deviation values of selected water-quality constituents and properties for selected springs in 

Texas, by ecoregion.

[Values in following order: mean; median; standard deviation from the mean. mg/L, milligrams per liter; na, not applicable; --, no values; μS/cm, microsiemens 

per centimeter at 25 degrees Celsius; °C, degrees Celsius] 

1 Alkalinity and hardness in milligrams per liter of calcium carbonate.

Level III

ecoregion

ID

Silica

(mg/L)

Calcium

(mg/L)

Magnesium

(mg/L)

Sodium

(mg/L)

Potassium

(mg/L)

Strontium

(mg/L)

Bicarbonate

(mg/L)

Sulfate

(mg/L)

Chloride

(mg/L)

23 10; 10; na 76; 76; na 26; 26; na 2; 2; na 0.5; 0.5; na --; --; -- 358; 358; na 5; 5; na 2; 2; na

24 21; 19; 8.6 182; 177; 107 72; 73; 63 356; 390; 299 15; 17; 8.9 3.6; 3.4; 2.3 258; 267; 37 497; 383; 519 389; 246; 448

25 19; 19; na 49; 49; 7.8 29; 28; 7.3 34; 32; 21 0.5; 0.5; na --; --; -- 308; 300; 49 146; 41; 254 296; 15; 617

26 35; 32; 15 178; 78; 281 33; 28; 37 543; 57; 2,398 3.8; 3.4; 2.7 0.3; 0.3; 0.08 260; 247; 91 490; 75; 1,091 1,664; 69; 6,487

27 29; 34; 12 214; 100; 222 63; 35; 70 299; 76; 675 1.2; 1.2; 1.1 --; --; -- 268; 259; 83 470; 112; 773 442; 56; 1,284

29 11; 12; 2.0 115; 110, 35 36; 34; 16 183; 83; 265 9.6; 4.6; 11 0.4; 0.4; 0.08 395; 410; 87 18; 12; 13 326; 141; 488

30 12; 11; 3.1 90; 90; 34 22; 18; 14 58; 8; 213 2.4; 1.3; 4.2 0.4; 0.3; 0.5 329; 323; 75 20; 13; 40 75; 13; 318

31 12; 12; 2.5 75; 75; 7.0 7; 7; 1.5 7; 6; 3.8 1.5; 0.9; 2.6 0.2; 0.2; 0.05 241; 244; 16 7; 7; 2.7 10; 10; 1.4

32 12; 12; 1.2 81; 80; 7.8 19; 17; 4.0 14; 10; 11 1.4; 1.4; 0.2 0.9; 0.7; 0.5 295; 288; 26 29; 27; 19 28; 21; 73

33 46; 16; 45 23; 14; 22 5; 2; 4.0 151; 69; 248 2.0; 1.2; 1.8 0.0; 0.0; 0.01 244; 44; 411 74; 24; 87 131; 64; 195

34 20; 20; 11 65; 51; 29 38; 25; 41 188; 97; 198 12; 12; na --; --; -- 262; 79; 337 86; 47; 112 298; 244; 244

35 23; 10; 26 1.4; 1; 1.1 1; 2; 0.7 7; 4; 5.9 0.1; 0.1; na --; --; -- 45; 12; 102 6; 2; 10 14; 6; 26

Level III

ecoregion

ID

Fluoride

(mg/L)

Nitrate

nitrogen

(mg/L)

pH

Dissolved

solids

(mg/L)

Alkalinity

(mg/L)1

Hardness

(mg/L)1

Specific

conductance

(μS/cm)

Temperature

 (°C)

23 0.3; 0.3; na 1.6; 1.6; na 7.5; 7.5; na 299; 299; na --; --; -- 296; 296; na --; --; -- --; --; --

24 1.6; 1.7; 0.9 5.7; 2.2; 8.1 7.4; 7.4; 0.4 1,610; 1,343; 1,422 213; 220; 29 663; 514; 509 2,628; 3,220; 1,867 25; 25; 5.6

25 1.5; 1.5; na 0.2; 0.2; na 8.0; 8.0; na 330; 318; 67 --; --; -- 243; 240; 39 --; --; -- 17; 17; 5.9

26 1.1; 0.6; 1.2 16; 20; 13 7.7; 7.6; 0.3 4,569; 468; 13,968 226; 221; 34 428; 232; 845 5,077; 869; 18,823 17; 18; 4.8

27 0.8; 0.6; 0.4 12; 12; 9.4 7.7; 7.6; 0.5 1,723; 670; 2,589 228; 222; 74 795; 397; 804 1,036; 880; 700 16; 19; 6.9

29 0.3; 0.2; 0.2 5.4; 5.7; 3.0 7.2; 7.2; 0.6 898; 616; 827 336; 368; 66 430; 408; 147 1,371; 1,090; 921 23; 22; 2.2

30 0.3; 0.2; 1.0 8.8; 8.1; 7.8 7.3; 7.3; 0.4 434; 324; 593 275; 270; 50 305; 290; 118 637; 582; 420 21; 22; 2.5

31 0.2; 0.2; 0.1 9.0; 8.2; 5.2 7.3; 7.3; 0.4 245; 245; 22 198; 200; 9.8 214; 214; 19 425; 429; 38 23; 23; 2.0

32 0.3; 0.2; 0.2 6.6; 5.9; 3.6 7.4; 7.3; 0.3 347; 350; 43 244; 241; 20 297; 300; 35 607; 604; 76 22; 22; 1.5

33 0.3; 0.1; 0.4 5.1; 2; 6.4 6.0; 5.4; 1.4 463; 443; 539 481; 79; 726 77; 44; 66 400; 138; 438 20; 21; 1.5

34 0.3; 0.3; na 6.5; 6.5; 3.5 7.2; 7.2; na 851; 483; 772 --; --; -- 323; 230; 234 --; --; -- --; --; --

35 0.1; 0.1; 0.0 4.0; 1.5; 4.7 5.7; 5.6; 0.8 40; 25; 38 --; --; -- 15; 10; 11 172; 34; 305 20; 19; 3.9
Table 8 31

Table 8

Table 9

Table 8. Minimum and maximum values of selected water-quality constituents and properties for selected springs in Texas, by 

ecoregion.

[Values in following order: minimum; maximum. mg/L, milligrams per liter; --, no values; μS/cm, microsiemens per centimeter at 25 degrees Celsius; 

°C, degrees Celsius] 

1 Alkalinity and hardness in milligrams per liter of calcium carbonate.

Level III

ecoregion

ID

Silica

(mg/L)

Calcium

(mg/L)

Magnesium

(mg/L)

Sodium

(mg/L)

Potassium

(mg/L)

Strontium

(mg/L)

Bicarbonate

(mg/L)

Sulfate

(mg/L)

Chloride

(mg/L)

23 10–10 76–76 26–26 1.7–1.7 0.5–0.5 -- 358–358 4.8–4.8 1.6–1.6

24 7.6–62 26–526 5.0–335 2.0–1,580 0.8–35 0.5–9.9 115–355 2.3–2,410 8.6–2,660

25 19–19 40–59 22–39 13–58 0.5–0.5 -- 265–366 12–600 6.0–1,400

26 12–68 40–1,210 5.0–179 8.0–11,800 0.5–8.2 0.2–0.4 115–560 7.0–4,400 5.4–32,000

27 10–47 16–617 6.0–233 27–2,582 0.5–2.0 -- 112–443 16–2,593 8.0–5,219

29 5.9–15 25–249 6.1–87 8.0–1,320 1.0–38 0.3–0.5 88–469 7.0–63 7.6–2,470

30 2.0–26 15–273 6.0–98 0.7–1,640 0.5–21 0.1–2.6 98–473 1.0–412 6.0–2,790

31 9.0–22 44–88 2.7–11 0.9–24 0.5–14 0.1–0.3 174–270 4.3–19 8.0–14

32 4.0–18 56–101 13–31 2.8–65 0.5–2.4 0.1–3.2 234–425 1.5–423 4.2–1,720

33 11–96 0.5–60 1.0–12 1.5–786 0.8–4.0 0.0–0.0 2.0–1,082 2.0–219 3.0–558

34 12–27 46–98 6.2–84 52–416 12–12 -- 55–651 3.0–247 63–640

35 6.0–52 0.1–2.5 0.5–2.0 1.6–16 0.1–0.1 -- 2.4–316 0.5–30 2.0–84

Level III

ecoregion

ID

Fluoride

(mg/L)

Nitrate

nitrogen

(mg/L)

pH

Dissolved

solids

(mg/L)

Alkalinity

(mg/L)1

Hardness

(mg/L)1

Specific

conductance

(μS/cm)

Temperature

 (°C)

23 0.3–0.3 1.6–1.6 7.5–7.5 299–299 -- 296–296 -- --

24 0.1–4.3 0.0–42 6.7–8.6 154–7,315 94–291 95–2,690 260–10,600 9.0–44

25 1.5–1.5 0.2–0.2 8.0–8.0 270–416 -- 207–284 -- 13–21

26 0.1–4.5 0.0–33 7.1–8.2 2.6–61,100 188–270 1.6–4,170 388–82,800 7.0–23

27 0.2–1.8 0.2–31 6.8–8.9 2.5–8,857 126–363 73–2,337 311–2,690 6.7–26

29 0.0–1.0 0.0–10 5.9–8.3 261–4,450 119–384 125–980 515–5,740 16–28

30 0.0–10 0.0–80 6.3–8.2 121–5,350 149–386 7.3–1,310 366–4,220 11–30

31 0.0–0.6 3.6–35 6.3–8.0 167–301 169–214 134–265 347–578 16–25

32 0.1–1.2 0.7–20 6.4–8.4 198–540 179–419 94–360 7.0–1,090 7.1–28

33 0.0–0.9 0.2–15 4.7–7.9 32–1,916 4.0–1,770 10–197 40–878 17–21

34 0.3–0.3 4.0–9.0 7.2–7.2 430–2,008 -- 150–590 -- --

35 0.0–0.1 0.2–10 4.6–7.0 12–122 -- 4.0–30 15–787 18–28
32 Regional Assessment of Historical Water Quality and Spring Flow for Selected Springs in Texas 

Table 9. Water-quality standards of selected constituents and properties.

[mg/L, milligrams per liter; EPA, U.S. Environmental Protection Agency; MCL, maximum contaminant level; NSDWR, National Secondary Drinking Water 

Regulations; CCC, criterion continuous concentration; CMC, criteria maximum concentration]

1 MCL is highest level of contaminant allowed in drinking water.

2 NSDWR is non-enforceable guideline regulating contaminants that might cause cosmetic effects (such as skin or tooth discoloration) or aesthetic effects 

(such as taste, odor, or color) in drinking water.

3 CCC is estimate of highest concentration of a material in surface water to which an aquatic community can be exposed indefinitely without resulting in an 

unacceptable effect.

4 CMC is estimate of highest concentration of a material in surface water to which an aquatic community can be exposed briefly without resulting in an 

unacceptable effect.

Constituent

or property

Standard

concentration Information Information source

Fluoride 4.0 mg/L EPA MCL1; potential health effects include bone 

disease and mottled teeth (in children) 

http://www.epa.gov/safewater/mcl.html#1

Nitrate nitrogen 10 mg/L EPA MCL1; potential health effects include 

serious illness and possible death for infants 

younger than 6 months

http://www.epa.gov/safewater/mcl.html#1

Chloride 250 mg/L EPA NSDWR2 http://www.epa.gov/safewater/mcl.html#1

Fluoride 2.0 mg/L EPA NSDWR2 http://www.epa.gov/safewater/mcl.html#1

pH 6.5–8.5 EPA NSDWR2 http://www.epa.gov/safewater/mcl.html#1

Sulfate 250 mg/L EPA NSDWR2 http://www.epa.gov/safewater/mcl.html#1

Dissolved solids 500 mg/L EPA NSDWR2 http://www.epa.gov/safewater/mcl.html#1

Alkalinity 20 mg/L EPA CCC3 http://www.epa.gov/waterscience/criteria/wqcriteria.html

Chloride 860 mg/L EPA CMC4 http://www.epa.gov/waterscience/criteria/wqcriteria.html

Chloride 230 mg/L EPA CCC3 http://www.epa.gov/waterscience/criteria/wqcriteria.html

Hardness 1,000 mg/L Common upper limit for use by chemical 

industry

http://www.epa.gov/waterscience/criteria/goldbook.pdf