June 14, 2016

DRAFT
Explanatory Report for the Proposed Desired Future Conditionsof the Western Fresh Edwards (Balcones Fault Zone) Aquifer
Groundwater Management Area 10

Table of Contents
Section ...................................................................................................................................... Page
APPENDICES .............................................................................................................................. iv
FIGURES ........................................................................................................................................v
TABLES ........................................................................................................................................ vi
1.

Groundwater Management Area 10 ................................................................................1

2.

Aquifer Description ...........................................................................................................1

3.

Desired Future Conditions ...............................................................................................2

4.

Policy Justification ............................................................................................................3

5.

Technical Justification ......................................................................................................3

6.

Consideration of Designated Factors ...............................................................................5
6.1
Aquifer Uses or Conditions ..................................................................................6
6.1.1
Description of Factors in the Western Fresh Edwards(Balcones Fault Zone) Aquifer in Kinney County ............................6
6.1.2
DFC Considerations.............................................................................6
6.2
Water-Supply Needs .............................................................................................6
6.2.1
Description of Factors in the Western Fresh Edwards(Balcones Fault Zone) Aquifer in Kinney County ............................6
6.2.2
DFC Considerations.............................................................................7
6.3
Water-Management Strategies ............................................................................8
6.3.1
Description of Factors in the Western Fresh Edwards(Balcones Fault Zone) Aquifer in Kinney County ............................8
6.3.2
DFC Considerations.............................................................................9
6.4
Hydrological Conditions ....................................................................................10
6.4.1
Description of Factors in the Western Fresh Edwards(Balcones Fault Zone) Aquifer in Kinney County ..........................10
6.4.1.1
Total Estimated Recoverable Storage ..............................................10
6.4.1.2
Average Annual Recharge ................................................................10
6.4.1.3
Inflows .................................................................................................11
6.4.1.4
Discharge ............................................................................................11
6.4.1.5
Other Environmental Impacts Including Springflow and
Groundwater/Surface Water Interaction ........................................12
6.4.2
DFC Considerations...........................................................................12

7.

Subsidence Impacts .........................................................................................................128.

Socioeconomic Impacts Reasonably Expected to Occur .............................................12

ii

8.1
8.2

Description of Factors in the Western Fresh Edwards (Balcones
Fault Zone) Aquifer in Kinney County ..............................................................12
DFC Considerations.............................................................................................13

9.

Private Property Impacts ...............................................................................................13
9.1
Description of Factors in the Western Fresh Edwards (Balcones
Fault Zone) Aquifer in Kinney County..............................................................13
9.2
DFC Considerations.............................................................................................13

10.

Feasibility of Achieving the DFCs .................................................................................14

11.

Discussion of Other DFCs Considered ..........................................................................14

12.

Discussion of Other Recommendations .........................................................................1412.1 Advisory Committees ..........................................................................................1412.2 Public Comments ............................................................................................14

13.

Any Other Information Relevant to the Specific DFCs ..............................................14

14.

Provide a Balance Between the Highest Practicable Level of Groundwater
Production and the Conservation, Preservation, Protection, Recharging, andPrevention of Waste of Groundwater and Control of Subsidence in the Management
Area ...................................................................................................................................14

15.

References .........................................................................................................................15

iii

List of Appendices
Appendix A—Proposed Desired Future Condition Resolution
Appendix B—Texas Water Development Board GAM Task xxxx (Revised): Total
Estimated Recoverable Storage for Aquifers in GMA 10
Appendix C—Socioeconomic Impacts Analyses for Regions K, L, and M

iv

FIGURES
Figure ....................................................................................................................................... Page
1

Map of the administrative boundaries of GMA 10 and Groundwater Conservation
Districts in GMA (From TWDB website) ............................................................................2

2

Discharge at Las Moras Springs (cfs) (red line) compared to water levels in the Well No. 70-38902 (ft, mean sea level) (blue line). Spring discharge data are taken from the U.S. Geological
Survey. Water elevation data are taken from the TWDB .............................................................. 5v

TABLES
Table ....................................................................................................................................... Page
1

DFCs for the western fresh Edwards (Balcones Fault Zone) Aquifer in GMA 10 ...............32

MAG for the Edwards (Balcones Fault Zone) Aquifer in GMA 10 in Kinney County.
Results are in acre-ft/yr and designated by river basin (Kinney County GCD, 2013) ........5

3

Estimated historical water use. TWDB historical water use survey data (Allen, 2013) (acre-ft/yr)64

Projected water demands. TWDB 2012 State Water Plan data (Allen, 2013) (acre-ft/yr) ............. 7

5

Projected water supply needs. TWDB 2012 State Water Plan data (Allen, 2013) (acre-ft/yr) ....... 7

6

Projected water-supply shortages in Kinney County under drought –of-record conditions
based on no new infrastructure development (Plateau Region Water Planning Group,2015) (acre-ft/yr) ..................................................................................................................87

Source water available after known demands are subtracted (Plateau Region Water
Planning Group, 2015) (acre-ft/yr) ......................................................................................98

Water-use categories where no water supply is available to meet its total need. These data
are not currently available in the Plateau Region Water Planning Group Plan (Plateau
Region Water Planning Group, 2015) (acre-ft/yr) ...............................................................99

Recommended and alternative water-management strategies that if implemented may
assist in meeting supply shortages (Plateau Region Water Planning Group, 2015) ............9

10

Total estimated recoverable storage for the fresh-water portion of the Edwards (Balcones Fault
Zone) Aquifer within Kinney County. Estimates are rounded within two significant numbers(Jones et al., 2013). ........................................................................................................................ 10

11

Summarized information for the Edwards (Balcones Fault Zone) Aquifer that is needed
for Kinney Count GCD’s Groundwater Management Plan. All values are approximate
and reported in acre-ft/yr (Hutchison et al., 2011).............................................................11vi

Abbreviations
DFC

Desired Future Conditions

GCD

Groundwater Conservation District

GMA

Groundwater Management AreaMAG

Modeled Available Groundwater

TWDB

Texas Water Development Board

vii

1.

Groundwater Management Area 10

Groundwater Management Areas (GMA) were created by the Texas Legislature to provide
for the conservation, preservation, protection, recharging, and prevention of waste of thegroundwater, and of groundwater reservoirs or their subdivisions, and to control
subsidence caused by withdrawal of water from those groundwater reservoirs or theirsubdivisions. Each GMA is charged with facilitating joint planning efforts in the GMAs within
its jurisdiction.
GMA 10 was created to oversee the Edwards (Balcones Fault Zone) and Trinity aquifers. Other
aquifers include the Leona Gravel, Buda Limestone, Austin Chalk, and the saline Edwards(Balcones Fault Zone) aquifers. The jurisdiction of GMA 10 includes all or parts of Bexar,
Caldwell, Comal, Guadalupe, Hays, Kinney, Medina, Travis, and Uvalde counties. GCDs in
GMA 10 include Barton Springs/Edwards Aquifer Conservation District, Comal Trinity GCD,
Edwards Aquifer Authority, Kinney County GCD, Medina County GCD, Plum Creek
Conservation District, and Uvalde County Underground Water Conservation District (UWCD)(Figure 1).
As mandated in Texas Water Code § 36.108, districts are required to submit DFCs of thegroundwater resources in their GMA to the executive administrator of the Texas Water
Development Board (TWDB), unless that aquifer is deemed to be non-relevant. According toTexas Water Code § 36.108 (d-3), the district representatives shall produce a DFCs Explanatory
Report for the management area and submit to the TWDB a copy of the Explanatory Report.
The fresh-water portion of the Edwards (Balcones Fault Zone) Aquifer located within Kinney
County is a major aquifer. The extent of this aquifer includes the fresh-water portion of the
Edwards (Balcones Fault Zone) Aquifer located within Kinney County (Figure 1). This
document is the Explanatory Report for the fresh-water portion of the Edwards (Balcones Fault
Zone) Aquifer located within Kinney County.
2.

Aquifer Description

For jurisdicational purposes, the fresh-water portion of the San Antonio segment of the Edwards(Balcones Fault Zone) Aquifer is defined as the fresh water portion of the Edwards (Balcones
Fault Zone) Aquifer located within Kinney County. The boundaries of the western fresh-water
Edwards (Balcones Fault Zone) Aquifer were determined using the Digital Geologic Atlas of
Texas (U.S. Geological Survey, 2005; Stoeser et al., 2005) and the GMA 10 boundary. The
geographic extent of the fresh-water portion of the Edwards (Balcones Fault Zone) Aquifer
located within Kinney County is available at the TWDB website
http://www.twdb.texas.gov/groundwater/models/gam/ebfz_s/ebfz_s.asp (Figure 2). As
illustrated, the jurisdiction is limited to the eastern portion of Kinney County. The western freshwater portion of the Edwards (Balcones Fault Zone) Aquifer is located entirely within the
Regional Water Planning Area J and the Kinney County GCD. The geographic extent of thewestern fresh-water Edwards (Balcones Fault Zone) Aquifer in the Kinney County GCD is
illustrated in Figures 1 and 2.

1

Figure 1. Map of the administrative boundaries of GMA 10 and GCDs in GMA (From TWDB
website)3.

Desired Future Conditions

GMA 10 incorporated information from the Kinney County GCD Groundwater Management
Plan and analyses from the TWDB during development of the proposed DFCs. The first cycle of

the Desired Future Condition for the western fresh Edwards (Balcones Fault Zone) Aquifer inKinney County in GMA 10 was that the water level in well 70-38-902 shall not fall below 1,184ft mean sea level (Table 1). This Desired Future Condition was described in Resolution No.
2010-11 and adopted August 23, 2010 by the GCDs in GMA 10.
The second cycle of the Desired Future Condition for the western fresh Edwards (Balcones Fault
Zone) Aquifer in Kinney County in GMA 10 remained the same as during the first cycle of DFCs,
that the water level in well 70-38-902 shall not fall below 1,184 ft mean sea level (Table 1). The
second cycle of the DFCs was adopted by the GCDs in GMA 10 on March 14, 2016 as Resolution
No. 2016-xx (Appendix A).

2

Table 1. DFCs for the western fresh Edwards (Balcones Fault Zone) Aquifer in GMA 10
Date Desired Future
AquiferDesired Future Condition Summary
Condition Adopted
Edwards
Water level in well number 70-38-902 shall
8/4/2010(Kinney County)
not fall below 1,184 feet mean sea level
Edwards
Water level in well number 70-38-902 shall?/?/2015(Kinney County)
not fall below 1,184 feet mean sea level
4.

Policy Justification

The Desired Future Condition for the San Antonio segment of the fresh-water Edwards(Balcones Fault Zone) Aquifer in Kinney County was adopted after considering factors identified
in Texas Water Code §36.108 (d):1.

Aquifer uses or conditions within the management area, including conditions that differ
substantially from one geographic area to another;a.
for each aquifer, subdivision of an aquifer, or geologic strata andb.
or each geographic area overlying an aquifer

2.

The water supply needs and water management strategies included in the state water
plan;

3.

Hydrological conditions, including for each aquifer in the management area the total
estimated recoverable storage as provided by the executive administrator, and the averageannual recharge, inflows, and discharge;

4.

Other environmental impacts, including impacts on spring flow and other interactions
between groundwater and surface water;

5.

The impact on subsidence;

6.

Socioeconomic impacts reasonably expected to occur;

7.

The impact on the interests and rights in private property, including ownership and therights of management area landowners and their lessees and assigns in groundwater asrecognized under Section 36.002;

8.

The feasibility of achieving the desired future condition; and,9.

Any other information relevant to the specific DFCs.

These factors are discussed in detail in appropriate sections in this Explanatory Report.
5.

Technical Justification

3

Technical justification for selection of the Desired Future Condition for the fresh-water portionof the Edwards (Balcones Fault Zone) Aquifer in Kinney County was provided by simulations
generated by a groundwater flow model developed for the Edwards (Balcones Fault Zone) Aquiferin Kinney County (Hutchison et al., 2011). The Kinney County groundwater model wasdeveloped by Hutchison et al. (2011) for use in management plan data analysis. The model wascalibrated to water-level and spring discharge data collected from 1950 to 2005; however, data
were extracted only for the period from 1980 to 2005 for the Kinney County GCD Groundwater
Management Plan (Kinney County GCD Groundwater Management Plan, 2013). These dates
were used to avoid skewing the data as a result of the drought of the 1950s. The period from1980 to 2005 includes both drought and wet climatic conditions.
Kinney County has two DFCs, one for GMA 7, which includes the western half of Kinney
County, and one for GMA 10, which includes the eastern half of Kinney County. The two DFCs
for Kinney County are separate, but both were specified for the same intent, to protect flow at
Las Moras Springs. GMA 7, which includes western Kinney County and Las Moras Springs,
designated as its Desired Future Condition that drawdown for the Edwards-Trinity Aquifer inwestern Kinney County be consistent with maintaining flow at Las Moras Springs at an annual
average flow of 23.9 cfs and a median flow of 24.4 cfs. GMA 10, which does not include Las
Moras Springs, used the Kinney County groundwater flow model developed by Hutchison et al.
(2011) to specify as its Desired Future Condition that the water level at Well No. 70-38-902 be
maintained at or above an elevation of 1,184 feet msl.
These two DFCs are essentially synonymous because Las Moras Springs discharge is wellcorrelated with groundwater elevation at Well No. 70-38-902 (Figure 2). The Desired Future
Condition of 1,184 ft msl at Well No. 70-38-902 was chosen by GMA 10 based on anassessment by TWDB that correlated groundwater elevation of 1,184 ft msl at Well No. 70-38902 to discharge of approximately 24 cfs at Las Moras Springs (Figure 3). Well No. 70-38-902 isalternatively identified as the Tularosa Well or the Tularosa Monitoring Well.
The DFCs for Kinney County were chosen to protect Las Moras Springs. The GMA Desired
Future Condition of an annual average flow of 23.9 cfs and a median flow of 24.4 cfs discharge
from the Las Moras Springs was chosen to represent pre-development conditions when thesprings did not go dry, or at least did not go dry as often as they did during the period during
which the number of irrigated acres were greatest. The GMA 10 Desired Future Condition which
specifies that the water level at Well No. 70-38-902 be maintained at or above an elevation of
1,184 ft msl was chosen for the same reasoning. The elevation of 1,184 ft msl has been
determined to correlate directly with Las Moras Springs discharge rate of 24.4 cfs.
The Modeled Available Groundwater (MAG) for the fresh-water portion of the Edwards(Balcones Fault Zone) Aquifer was calculated by the TWDB (Shi et al., 2012) and provided in
GAM Run 12-002 MAG (Shi, 2012). The new model run is identified as an update of Scenario 3of Groundwater Availability Modeling (revised) Task 10-027 (Hutchison, 2011). The model runs
were based on the MODFLOW-2000 model developed by the TWDB to assist with the joint
planning process regarding the Kinney County GCD (Hutchison et al., 2011). In both model
runs, the total pumping in Kinney County was maintained at approximately 77,000 acre-feet per
year to achieve the Desired Future Condition. The MAG for the GMA 10 portion of Kinney4County is 6,321 acre-ft/yr (Table 2). Details regarding this model run are summarized in Shi etal. (2012).
100
90
1205

80
70

1200

60
1195

50
40

1190

30
20

1185

10
1180

Las Moras Springs Discharge (cfs)

Water-Level Elevation 70-38-902 (ft, msl)

1210

0

Date
Figure 2. Discharge at Las Moras Springs (cfs) (red line) compared to water levels in the Well
No. 70-38-902 (ft, mean sea level) (blue line). Spring discharge data are taken from the U.S.
Geological Survey. Water elevation data are taken from the TWDB.
Table 2. MAG for the Edwards (Balcones Fault Zone) Aquifer in GMA 10 in Kinney County.
Results are in acre-ft/yr and designated by river basin (Kinney County GCD, 2013).
Year
River Basin
2010
2020
2030
2040 2050 2060
Nueces6,319
6,319
6,319 6,319 6,319 6,319
Rio Grande
2
2
2
2
2
2
Total
6,321
6,321
6,321 6,321 6,321 6,321
6.

Consideration of Designated Factors

According to Texas Water Code § 36.108 (d-3), the district representatives shall produce a
Desired Future Condition Explanatory Report. The report must include documentation of how
factors identified in Texas Water Code §36.108 (d) were considered prior to proposing a Desired
Future Condition, and how the proposed Desired Future Condition impacts each factor. The
following sections of the Explanatory Report summarize the information that Kinney County
GCD used in its deliberations and discussions.
56.1

Aquifer Uses or Conditions

6.1.1

Description of Factors in the Western Fresh Edwards (Balcones Fault Zone) Aquiferin Kinney County
The information in this section was prepared by the Groundwater Technical Assistance Sectionof the Groundwater Resources Division at the TWDB (Allen, 2013). This information is also
included as an appendix in the Kinney County Conservation District Groundwater Management
Plan (Kinney County Conservation District, 2013). Groundwater use within the Kinney County
Conservation District is comprised primarily of pumpage and use from the fresh-water portion of
the Edwards (Balcones Fault Zone) Aquifer with a much smaller component of pumpage comingfrom the Trinity Aquifer. The estimated historical surface-water and groundwater use in Kinney
County for the period 2006-2007 is presented in Table 3.
Table 3. Estimated historical water use. TWDB historical water use survey data (Allen, 2013)(acre-ft/yr).
ManuSteam
LiveYear
SourceMunicipal
Irrigation Mining
Total
facturing Electric
stock
GW
1,126
0
0
4,776
0
238
6,410
2006
SW
0
0
0
0
0
60
60
GW
906
0
0
1,641
0
217
2,764
2007
SW
0
0
0
0
0
55
55
GW
1,101
0
0
2,043
0
294
2,438
2008
SW
0
0
0
0
0
73
73
GW
1,164
0
0
895
0
338
2,397
2009
SW
0
0
0
0
0
84
84
GW
1,026
0
0
1,258
0
184
2,468
2010
SW
0
0
0
0
0
46
46
6.1.2 DFC Considerations
The dominant use of the aquifer by pumping is public water supply, and the sustainability of that
supply, especially for users who have no alternative supply physically or economically available
and/or who are in vulnerable locations, must be protected to the extent feasible (Texas Water
Code §36). The primary concern with sustainability of this karst aquifer groundwater supply isdrought, notably extreme drought that stresses the entire aquifer. The DFCs supports and is, infact, the linchpin of a drought-management program to promote long-term sustainability of bothspringflow and water supplies.
6.2

Water-Supply Needs

6.2.1

Description of Factors in the Western Fresh Edwards (Balcones Fault Zone) Aquiferin Kinney County
The information in this section was prepared by the Groundwater Technical Assistance Sectionof the Groundwater Resources Division at the TWDB (Allen, 2013). This information is also
6included as an appendix in the Kinney County Conservation District Groundwater Management
Plan (Kinney County Conservation District, 2013). The TWDB provides water-supply needs
estimates by decade as well as by water-user group basin. There are two major basins in Kinney
Count; the Nueces River basin and the Rio Grande basin. Summaries of the projected watersupply demands and needs in acre-ft/yr are provided by decade in the Table 4 and 5 for eachwater-user group and each water-user group basin. As illustrated, the projected water-supply
demands and needs are greater than the estimated historical water use for the years 2006-2010(Table 3).
Table 4 Projected water demands. TWDB 2012 State Water Plan data (Allen, 2013) (acre-ft/yr).
WUG
WUG Basin
2010
2020
2030
2040
2050
2060
Irrigation
Nueces
338
323
310
296
284
271
Livestock
Nueces
187
187
187
187
187
187
County-other
Nueces
35
21
13
8
4
3
Brackettville
Rio Grande
583
583
582
582
581
582
County-other
Rio Grande
32
31
31
31
31
31
Irrigation
Rio Grande
13,169 12,605 12,063 11,547 11,053 10,582
Live Stock
Rio Grande
258
258
258
258
258
258
Fort Clark Springs MUD
Rio Grande
626
653
678
704
723
727
Sum of Projected Water Demands
15,228 14,661 14,122 13,613 13,121 12,641
Table 5. Projected water supply needs. TWDB 2012 State Water Plan data (Allen, 2013) (acreft/yr).
WUG
WUG Basin
2010
2020
2030
2040
2050
2060
Irrigation
Nueces
4,044
4,059
4,072
4,086
4,098
4,111
Livestock
Nueces
147
147
147
147
147
147
County-other
Nueces
13
27
35
40
44
45
Brackettville
Rio Grande
64
64
65
65
66
65
County-other
Rio Grande
56
57
57
57
57
57
Irrigation
Rio Grande
12,615 13,179 13,721 14,237 14,731 15,202
Livestock
Rio Grande
83
83
83
83
83
83
Fort Clark Springs Mud
Rio Grande
494
467
442
416
397
393
Sum of Projected Water Supply Needs
17,516 18,083 18,622 19,131 19,623 20,103
6.2.2 DFC Considerations
The dominant use of the Edwards (Balcones Fault Zone) Aquifer within the Kinney County
GCD in GMA 10 by pumping is domestic use and irrigation, and the sustainability of that
supply, especially for users who have no alternative supply physically or economically available
and/or who are in vulnerable locations, must be protected to the extent feasible (Texas Water
Code §36). The primary concern with sustainability of this karst aquifer groundwater supply isdrought, notably extreme drought that stresses both aquifers. The DFC supports and is, in fact,
the primary concern with sustainability of this karst aquifer groundwater supply is drought,
notably extreme drought that stresses both aquifers. The DFC supports and is, in fact, the7linchpin of a drought management program to promote long-term sustainability of watersupplies.
6.3

Water-Management Strategies

6.3.1 Description of Factors in the Western Fresh Edwards (Balcones Fault Zone)
Aquifer in Kinney County
The following information is from the Plateau Region Initially Prepared Water Plan (Plateau
Region Water Planning Group, 2015). A major component of the Plateau Region InitiallyPrepared Water Plan is to identify municipalities and water-use categories that may, in times ofsevere drought, be unable to meet expected water-supply needs based on today’s ability toaccess, treat, and distribute the supply. A goal of the Plateau Region Initially Prepared Water
Plan is to provide for the health, safety, and welfare of the human community, with as little
detrimental effect to the environment as possible. Recreation activities involve human interaction
with the outdoor environment and are often directly dependent on water resources. It is
recognized that the maintenance of the regional environmental community’s water supply needs
serves to enhance the lives of citizens of the Plateau Region as well as the tens of thousands ofannual visitors to this Region. The implementation of water-management strategies
recommended in the Plateau Region Initially Prepared Water Plan is not expected to have any
impact on native-water quality. In particular, primary and secondary safe drinking water
standards, which are the key parameters of water quality identified by the Plateau Region Water
Planning Group as important to the use of the water resource, are not compromised by the
implementation of the strategies. Also, no recommended strategies involve moving water from arural location for use in an urban area.
The data presented in this section are provided by the Plateau Region Water Planning Group
Plan (Plateau Region Water Planning Group, 2015). Recommended alternatives, or watermanagement strategies, to meet anticipated drought-induced shortages are presented in the
Plateau Region Initially Prepared Water Plan for consideration. Table 6 lists the projected watersupply shortages in Kinney County under drought-of-record conditions based on no new
infrastructure development. Table 7 lists source water available after known demands are
subtracted. Table 8 identifies water-use categories where no water supply is available to meet its
total need. As noted, these data are not currently available in the Plateau Region Water PlanningGroup Plan. Table 9 provides a listing of all recommended and alternative water management
strategies in the Plateau Region Water Planning Group Plan that if implemented may assist inmeeting supply shortages.
Table 6. Projected water-supply shortages in Kinney County under drought –of-record
conditions based on no new infrastructure development (Plateau Region Water Planning Group,2015) (acre-ft/yr)
WUG/WWP Basin
2020
2030
2040
2050
2060
2070
Rio
Livestock
22
22
22
22
22
22
Grande8

Table 7. Source water available after known demands are subtracted (Plateau Region Water
Planning Group, 2015) (acre-ft/yr)
Groundwater Basin
Salinity
2020
2030
2040
2050
2060
2070
Austin Chalk
Rio
Brackish 4,045
4,045
4,045
4,045
4,045
4,045
Aquifer
GrandeEdwards(Balcones
Nueces
Fresh
3.434
3.434
3.434
3.434
3.434
3.434
Fault Zone)
Aquifer
Edwards(Balcones
Rio
Fresh
2
2
2
2
2
2
Fault Zone)
GrandeAquiferTable 8. Water-use categories where no water supply is available to meet its total need. These
data are not currently available in the Plateau Region Water Planning Group Plan (Plateau
Region Water Planning Group, 2015) (acre-ft/yr)
WUG/WWP Basin
2020
2030
2040
2050
2060
2070
Table 9. Recommended and alternative water-management strategies that if implemented may
assist in meeting supply shortages (Plateau Region Water Planning Group, 2015)
Water
Water
Strategy Supply (acre-ft/yr)
Total
Utility
Management
Capital2020
2030 2040 2050 2060 2070
Group
Strategy
Cost
City ofConservation:
58
58
58
58
58
58
$1,116
Brackettville Water loss audit andmain-line repair
Increase supply to
3
3
3
3
3
3
$751,000
Spoford with newwater line
Increase storage
3
3
3
3
3
3
$288,000
facility
Ft Clark
Increase storage
620
620
620
620
620
620 $1,033,000
Springs
facility
MUD
KinneyConservation:
145
145
145
145
145
145
$0
CountyVegetative
Other
management _Arundo donax
KinneyAdditional water
20
20
20
20
20
20
$55,000
Countywells
Livestock
6.3.2 DFC Considerations

9

The DFC under consideration here is specific to the Edwards (Balcones Fault Zone) Aquifer
within the Kinney County GCD in GMA 10. The DFC for the Edwards (Balcones Fault Zone)
Aquifer within the Kinney County GCD in GMA 10, as described above, underpins an aquiferresponsive drought management program that encourages both full-time water conservation andfurther temporary curtailments in pumping during drought periods that increase with drought
severity.
6.4

Hydrological Conditions

6.4.1 Description of Factors in the Western Fresh Edwards (Balcones Fault Zone) Aquiferin Kinney County
6.4.1.1 Total Estimated Recoverable Storage
Texas statute requires that the total estimated recoverable storage of relevant aquifers be
determined. Total estimated recoverable storage is a calculation provided by the TWDB. Texas
Administrative Code Rule §356.10 (Texas Administrative Code, 2011) defines the total
estimated recoverable storage as the estimated amount of groundwater within an aquifer that
accounts for recovery scenarios that range between 25 percent and 75 percent of the porosityadjusted aquifer volume. As described in GAM Task 13-033 (Jones et al., 2013), the total
recoverable storage estimated for the Edwards (Balcones Fault Zone) Aquifer within the Kinney
County GCD in GMA 10 is listed in Table 10. Total estimated recoverable storage values may
include a mixture of water-quality types, including fresh, brackish, and saline groundwater,
because the available data and the existing Groundwater Availability Models do not permit thedifferentiation between different water-quality types. The total estimated recoverable storage
values do not take into account the effects of land surface subsidence, degradation of water
quality, or any changes to surface-water/groundwater interaction that may occur due to pumping.
Table 10. Total estimated recoverable storage for the fresh-water portion of the Edwards(Balcones Fault Zone) Aquifer within Kinney County. Estimates are rounded within two
significant numbers (Jones et al., 2013).
Total Storage
25 percent of Total Storage
75 percent of Total Storage(acre-ft)(acre-ft)(acre-ft)
3,100,000
775,000
2,325,000
6.4.1.2 Average Annual Recharge
Shi and Wade (2013) calculated the average annual recharge of the Edwards (Balcones Fault
Zone) Aquifer in Kinney County using the Kinney County alternative Groundwater Availability
Model (Hutchison et al., 2011). The alternative Groundwater Availability Model encompassed
all of Kinney County, thus the analysis included both GMAs 7 and 10 in Kinney County. As
presented in Table 11, recharge to the Edwards (Balcones Fault Zone) Aquifer in Kinney County
was calculated to be 17,674 acre-ft/yr.

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Table 11. Summarized information for the Edwards (Balcones Fault Zone) Aquifer that isneeded for Kinney Count GCD’s Groundwater Management Plan. All values are approximate
and reported in acre-ft/yr (Hutchison et al., 2011).
Management Plan
TWDB Kinney GCD Model
Aquifer and other units
requirement(1980 – 2005)
Estimated annual amount of
Edwards (Balcones Fault
recharge from precipitation to
17,674Zone) Aquifer
the district
Estimated annual volume ofwater that discharges from the
Edwards (Balcones Fault
aquifer to springs and any
514Zone) Aquifer
surface water body including
lakes, streams, and rivers
Estimated annual volume of
Edwards (Balcones Fault
flow into the district within
268Zone) Aquifer
each aquifer in the district
Estimated annual volume of
Edwards (Balcones Fault
flow out of the district within
12,346Zone) Aquifer
each aquifer in the district
From Upper Cretaceous Units
to Edwards (Balcones Fault
15,597Zone) Aquifer
From Edwards-Trinity
Estimated net annual volume(Plateau) Aquifer to Edwardsof flow between each aquifer
11,514(Balcones Fault Zone)
in the district
Aquifer
From Edwards (Balcones
Fault Zone) Aquifer to
33,598
Edwards-Trinity Units
6.4.1.3 Inflows
Shi and Wade (2013) calculated inflows to the Edwards (Balcones Fault Zone) Aquifer inKinney County using the Kinney County alternative Groundwater Availability Model (Hutchison
et al., 2011). The alternative Groundwater Availability Model encompassed all of Kinney
County, thus the analysis included both GMAs 7 and 10 in Kinney County. As presented inTable 5, inflows to the Edwards (Balcones Fault Zone) Aquifer in Kinney County were
calculated to be 268 acre-ft/yr.
6.4.1.4 Discharge
Shi and Wade (2013) calculated inflows to the Edwards (Balcones Fault Zone) Aquifer inKinney County using the Kinney County alternative Groundwater Availability Model (Hutchison
et al., 2011). The alternative Groundwater Availability Model encompassed all of Kinney
County, thus the analysis included both GMAs 7 and 10 in Kinney County. As presented inTable 5, the estimated annual volume of water that discharges from the aquifer to springs and11any surface water body including lakes, streams, and rivers from the Edwards (Balcones Fault
Zone) Aquifer in Kinney County was calculated to be 514 acre-ft/yr. the estimated annual
volume of flow out of the district within each aquifer in the district from the Edwards (Balcones
Fault Zone) Aquifer in Kinney County was calculated to be 12,346 acre-ft/yr.
6.4.1.5 Other Environmental Impacts Including Springflow and Groundwater/Surface-Water
Interaction
Shi and Wade (2013) calculated inflows to the Edwards (Balcones Fault Zone) Aquifer inKinney County using the Kinney County alternative Groundwater Availability Model (Hutchison
et al., 2011). The alternative Groundwater Availability Model encompassed all of Kinney
County, thus the analysis included both GMAs 7 and 10 in Kinney County. As presented inTable 5, the net annual volume of flow between each aquifer in the district the Edwards(Balcones Fault Zone) Aquifer in Kinney County was calculated to be: (i) 15,597 acre-ft/yr
from Upper Cretaceous Units to Edwards (Balcones Fault Zone) Aquifer; (ii) 11,514 acre-ft/yr
from Edwards-Trinity (Plateau) Aquifer to Edwards (Balcones Fault Zone) Aquifer; and (iii)
33,598 acre-ft/yr from Edwards (Balcones Fault Zone) Aquifer to Edwards-Trinity Units.
6.4.2 DFC Considerations
The DFC is proposed on the basis that Edwards (Balcones Fault Zone) Aquifer in Kinney
County is hydrologically a classic karst aquifer, with temporally variable inflows from various
recharge sources and major natural discharge points at Las Moras, Pinto, and Mud springs thatare also temporally variable with aquifer conditions. This hydrologic condition denotes that it ishighly vulnerable to drought, and water supplies are substantially adversely affected by drought.
Additionally, the geologic strata that form the aquifer dip regionally to the south, such that boththe saturated thickness in the unconfined zone and the artesian pressure head in the confinedzone are larger to the south. However, while faulted, the aquifer is well-integratedhydrologically and has a common potentiometric surface throughout the subdivision.
Springflows at Las Moras, Pinto, and Mud springs are directly and essentially solely related tothe elevation of the potentiometric surface, regardless of the different thickness and depth ofgroundwater that exists in various parts of the subdivision or other hydrologic conditions, except
as they affect the potentiometric surface. Preservation of minimal springflows at Las Moras,
Pinto, and Mud springs are expressly designed to provide that level of environmental andecological protection.
7.

Subsidence Impacts

Subsidence has historically not been an issue with the Edwards (Balcones Fault Zone) Aquifer inKinney County in GMA 10.
8.

Socioeconomic Impacts Reasonably Expected to Occur

8.1.

Description of Factors in the Western Fresh Edwards (Balcones Fault Zone) Aquiferin Kinney County
12Administrative rules require that regional water planning groups evaluate the impacts of not
meeting water needs as part of the regional water planning process, and rules direct TWDB staff
to provide technical assistance [§357.7 (4)(A)]. Staff of the TWDB’s Water Resources Planning
Division designed and conducted a report in support of the Plateau Region Water PlanningGroup (Region J). The report “Socioeconomic Impacts of Projected Water Shortages for the
Plateau Region Water Planning Area (Region J)” was prepared by the TWDB in support of the2011 Plateau Region Water Plan.
The report on socioeconomic impacts summarizes the results of the TWDB analysis anddiscusses the methodology used to generate the results for Region J. The socioeconomic impact
report for Water Planning Group L is included in Appendix C.
8.2.

DFC Considerations

Because none of the water-management strategies involve changes in the current use of thewestern fresh Edwards (Balcones Fault Zone) Aquifer in Kinney County, as described in Section
6.3, the proposed DFCs do not have a differential socioeconomic impact. They are supportive of
the status quo in this regard, which is considered positive.
9.

Private Property Impacts

9.1

Description of Factors in the Western Fresh Edwards (Balcones Fault Zone) Aquiferin Kinney County
The impact on the interests and rights in private property, including ownership and the rights of
GMA landowners and their lessees and assigns in groundwater is recognized under Texas Water
Code Section 36.002. The legislature recognizes that a landowner owns the groundwater below
the surface of the landowner's land as real property. Nothing in this code shall be construed as
granting the authority to deprive or divest a landowner, including a landowner's lessees, heirs, orassigns, of the groundwater ownership and rights described by this section.
Texas Water Code Section 36.002 does not: (1) prohibit a district from limiting or prohibiting thedrilling of a well by a landowner for failure or inability to comply with minimum well spacing or
tract size requirements adopted by the district; (2) affect the ability of a district to regulate
groundwater production as authorized under Section 36.113, 36.116, or 36.122 or otherwise
under this chapter or a special law governing a district; or (3) require that a rule adopted by a
district allocate to each landowner a proportionate share of available groundwater for production
from the aquifer based on the number of acres owned by the landowner.
9.2

DFC Considerations

The DFC is designed to protect the sustained use of the aquifer as a water supply for all users inaggregate. The DFC does not prevent use of the groundwater by landowners either now or in the
future, although ultimately total use of the groundwater in the aquifer is restricted by the aquifer

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condition, and that may affect the amount of water that any one landowner could use, either atparticular times or all of the time.
10.

Feasibility of Achieving the DFCs

The feasibility of achieving a Desired Future Condition directly relates to the ability of theKinney County GCD and GMA 10 to manage the fresh-water portion of the Edwards (Balcones
Fault Zone) Aquifer in Kinney County to achieve the DFCs. The feasibility of achieving this goalis limited by the finite nature of the resource and how it responds to drought and the pressuresplaced on this resource by economic and population growth within the area served by thisresource and the potential that water is exported out of the Kinney County GCD. Texas State law
provides GCDs and GMAs with the responsibility and authority to conserve, preserve, andprotect these resources and to insure for the recharge and prevention of waste of groundwaterand control of subsidence in the management area. The feasibility of achieving these goals could
be altered if state law is revised or interpreted differently than is currently the case.
11.

Discussion of Other DFCs ConsideredNo other Desired Future Condition of the western fresh Edwards (Balcones Fault Zone) Aquifer
was considered.
12.

Discussion of Other Recommendations

12.1

Advisory Committees

An Advisory Committee for GMA 10 has not been established.
12.2

Public Comments

Each GCD must hold a public meeting within 90 days after the GMA approves its DFCs. During
this meeting, the GCD needs to document stakeholder input. This input is to be submitted by areport from the GCD to the GMA within 90 days after the GMA approves its Desired Future
Condition.
The Kinney County Groundwater Management District has not yet approved its DFCs. The
Kinney County GCD has not yet held public meetings to gather public comment on the DFCs.
No public comments have yet been offered regarding the Desired Future Condition for the freshwater portion of the Edwards (Balcones Fault Zone) Aquifer in Kinney County.
13.

Any Other Information Relevant to the Specific DFCs

No additional information relevant to the specific DFCs has been identified.
14.
Provide a Balance Between the Highest Practicable Level of Groundwater
Production and the Conservation, Preservation, Protection, Recharging, and Prevention ofWaste of Groundwater and Control of Subsidence in the Management Area
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TWDB has not developed guidance on how to approach this factor. It is up to the wishes of the
GCD s on how they wish to approach it, whether in a qualitative, quantitative, or combinationmanner. But, the GCDs need to include stakeholder input so that this factor can be satisfactory
addressed. Participation by the project team at town hall meetings or with individual GCDs is
not included in the scope of this work. GCD management plans will be used to complete thisrequirement.
Each GCD must hold a public meeting within 90 days after the GMA approves its DFCs. During
this meeting, the GCD needs to document stakeholder input regarding whether the DFCs provide
a balance between the highest practicable level of groundwater production and the conservation,
preservation, protection, recharging, and prevention of waste of groundwater and control ofsubsidence in the management area. This input is to be submitted by a report from the GCD to
the GMA within 90 days after the GMA approves its DFCs.
15.

References

Allen, S. 2013. Estimated historical water use and 2012 State Water Plan datasets: Kinney
County Groundwater Conservation District. Texas Water Development Board. Groundwater
Resources Division. Groundwater Technical Assistance Section.
Hutchison, W.R. 2011. GAM Task 10-027 (revised): Texas Water Development Board, GAM
Task 10-027 Report. 8 p.
Hutchison, W.R., J. Shi, and M. Jigmond. 2011. Groundwater Flow Model of the Kinney County
Area, Texas Water Development Board. 138 p.
Jones, I.C., J. Shi, and R. Bradley. 2013. GAM Task 13-033: Total estimated recoverable storage
for aquifers in Groundwater Management Area 10.
Kinney County Groundwater Conservation District. 2013. Kinney County Groundwater
Conservation District Groundwater Management Plan.
Plateau Region Water Planning Group. 2015. Plateau Region Initially Prepared Water Plan.
Shi, J. 2012. GAM Task Report 12-002: Modeled Available Groundwater in Kinney County(July 24, 2012).
Shi, J., C. Ridgeway, and L. French. 2012. Draft GAM Task Report 12-002: Modeled Available
Groundwater in Kinney County (April 11, 2012).
Shi, J. and S. Wade. 2013. GAM Run 12-014: Kinney County Groundwater Conservation
District Management Plan. 11 p.
Stoeser, D.B., N. Shock, G.N. Green, G.M. Dumonceaux, and W.D. Heran. 2005. A Digital
Geologic Map Database for the State of Texas: U.S. Geological Survey Data Series 170.
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U.S. Geological Survey. 2005. Preliminary integrated geologic map databases for the UnitedStates: Central states: Montana, Wyoming, Colorado, New Mexico, North Dakota, South
Dakota, Nebraska, Kansas, Oklahoma, Texas, Iowa, Missouri, Arkansas, and Louisiana. GS
Open-File Report 2005-1351. http://pubs.usgs.gov/of/2005/1351/ .

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