Welcome To The Fourth Stakeholders Advisory Forum€¦ · In The Edwards-Trinity (Plateau) Aquifer...

Welcome To The FourthEdwards-Trinity Aquifer ModelStakeholders Advisory Forum

ET SAF 4June 25, 2002

Texas Water Development BoardGroundwater Availability Modeling

A Groundwater Flow Model forthe Edwards-Trinity Aquifer of

West-Central, Texas

Roberto AnayaTexas Water Development Board

• Provide Public Awareness of GAM• Update Interested Participants• Solicit Data and Information• Encourage Comments and Criticism

Edwards-Trinity StakeholdersAdvisory Forum Objectives

Spatial Extent Of TheEdwards-Trinity Model

Stratigraphic Units

Modified From Barker and Ardis, 1996

Vertical Profile Of The Edwards-Trinity Aquifer Sediments

Fort Lancaster Fm. Segovia Fm.

Fort Terrett Fm.

Glen Rose LimestoneBasalCretaceous Sand

Pre-Cretaceous Rocks

Maxon Sand

Hensel SandCow Creek LimestoneHammett Shale

Hosston Fm.

Sligo Fm.

NW SESonora

Modified From Barker and Ardis, 1996

Pre-DevelopmentGroundwater Conditions

• First winter measurement for each well site inTWDB database excluding 50s drought

• Water level measurements selected from pre-1980• Trintity potentiometric surface• Fredericksburg/Edwards potentiometric surface• Composite Edwards-Trinity potentiometric surface

Trinity PredevelopmentWater Levels (Prior to 1980)

Earliest Winter Measurements Excluding 50’ Drought

Edwards PredevelopmentWater Levels (Prior to 1980)


Edwards-Trinity PredevelopmentWater Levels (Prior to 1980)


Surface Hydrology

• MODFLOW drain package will be used to modelmajor springs

• MODFLOW stream-routing package will be usedto model major rivers

• MODFLOW reservoir package will be used tomodel reservoirs

USGS Surface Water Gage Sites

Major Rivers

TWDB Database Spring Locations

Major Reservoirs

Drain Cells - Irion and Tom Green Counties

Springs in Concho River Basin

Pecos River

Stream Cells - Crockett, Pecos, andTerrell Counties

Amistad Reservoir

Reservoir Cells - Val Verde County

Lunch Time!

www.twdb.state.tx.us/gam

FOR MORE INFO VISIT...

We will reconvene to finish thediscussion of the Edwards-TrinityAquifer Model

90 Minute Break

Conceptual Model andBoundary Conditions

• 3 layers proposed for the model• Top layer number 1 will be used to model

Edwards-Trinity cap rocks• Emphasis will be placed on bottom 2 layers• General-head boundary will be used for layer 3

cells to represent the hydraulic connection withunderlying and lateral aquifers

Proposed Model Layers for theEdwards-Trinity Aquifer Model


Fort Terrett Fm.

NW SEOzona

Cenozoic Rocks Upper KLayer 1

Layer 2

Layer 3

Model Layers


Maxon Sand

Hammett ShaleHosston Fm.


Sligo Fm.

Hensel SandCow Creek Limestone

Spatial Extent of theEdwards-Trinity Sediments

Spatial Extent of theTrinity-Hill Country Sediments

Spatial Extent of theTrinity-Hill Country Model

Spatial Extent of thePecos Alluvium Sediments

Extent of Model Layer 3

Extent of Model Layers 1, 2, & 3

Proposed Model Layers for theEdwards-Trinity Aquifer Model


Fort Terrett Fm.

NW SEOzona

Cenozoic Rocks Upper KLayer 1

Layer 2

Layer 3

Model Layers


Maxon Sand

Hammett ShaleHosston Fm.


Sligo Fm.

Hensel SandCow Creek Limestone

Lateral Geology at Edges ofEdwards-Trinity

Cenozoic PecosAlluvium

Ogallala

Lipan

Edwards BFZ

TrinityHill Country

Overlying Geology ofEdwards-Trinity Aquifer

Cenozoic PecosAlluvium

Ogallala

Underlying Geology at Base ofEdwards-Trinity Aquifer

RustlerDockum

Capitan

Ellenburger-San Saba

Hickory

Current Structural Geometryof the Edwards-Trinity Model

• Data sources included USGS, BEG GAT sheets,report cross-sections, and a few well logs

• All data was compiled into point locations• All data was then checked for outlier significance• A trial and error technique was used to interpolate

structural surfaces with advance geostatisticalmethods

Structural Base ofEdwards-Trinity Sediments

From - USGS unpublished data, 2001

Structural Base of Trinity

Bottom of Layer 3 Control Data

Structural Base of Trinity

Bottom of Layer 3

Structural Base For Edwards Group

From Barker and Ardis, 1996

Structural Base ofEdwards Sediments

Adapted From - Barker and Ardis, 1996

Structural Base of Fredericksburg/Edwards

Bottom of Layer 2 Control Data

Structural Base of Fredericksburg/Edwards

Bottom of Layer 2

Difference Between Layer 2 and Layer 3

Layer 2 - Layer 3

Structural Top ofEdwards-Trinity Sediments

From - USGS unpublished data, 2001

Topographic Surface

3 Arc Second DEM

Questions or Comments?



We will reconvene for a few more minutesto finish discussion on model grid andpumping test status

15 Minute Break!

Development of Model Gridfor Edwards-Trinity Model

• 300 X 400 cell grid• Rotated 42 degrees east of north (clockwise)• 1 mile X 1mile cells• 120,000 square miles• Largest of all the GAM grids

Edwards-Trinity 300X400 Model Grid

120,000 Square miles

Model Grid Relative to Crockett County

Layer 3 Foot Print

Layer 2 Foot Print

Layer 1 Foot Print

Status of Pumping Tests andHydraulic Properties

• TWDB goal of 39 new pumping tests will be metas part of the Edwards-Trinity GAM initiative

• TWDB groundwater database searched for specificcapacity tests

• TNRCC specific capacity tests acquired• Additional pumping tests were selected from

literature review

Pumping Tests from Current TWDB GAM

35 Tests Completed with 4 More Currently Underway

Specific Capacity Tests from TWDB Database

About 369 Tests Found

Specific Capacity Tests from TNRCC


Pumping Tests from Literature Review


Data Density for Hydraulic Properties

Over 1350 Data Points Expected

Current Project Status• Completed Literature Review• Finalization of Conceptual Model• Finalization of Structure Geometry• Completed 36 of 39 New Pumping Tests• Finalization of ALL Data Collection• Steady-State Water Levels Analysis• Continued Data Processing and Analysis

Potential Topics For ET SAF 5

• Final Structural Geometry• Final Hydraulic Property Distributions• Introduce Pumpage Distributions• Introduce Methods for Recharge and

Evapotranspiration Estimates• Steady-State Calibrations Methods

Primary Literature Sources• R. A. Barker and A. F. Ardis, Hydrogeologic Framework of the

Edwards-Trinity Aquifer System, West-Central Texas, USGSProfessional Paper 1421-B, 1996.

• L. E. Walker, Occurrence, Availability, and Chemical Quality ofGroundwater In The Edwards Plateau Region of Texas, TexasDepartment of Water Resources Report 235, 1979.

• R. Rees and A. W. Buckner, Occurrence and Quality of GroundwaterIn The Edwards-Trinity (Plateau) Aquifer in the Trans-Pecos Regionof Texas, Texas Department of Water Resources Report 255, 1980.

• E. L. Kuniansky and K. Q. Holligan, Simulation of Flow in theEdwards-Trinity Aquifer System and Contiguous HydraulicallyConnected Units, West-Central Texas, USGS Water-ResourcesInvestigation Report 93-4039, 1994.

Questions or Comments?End of ET SAF 4!

Have a safe drive home ...



A U.S.-MexicoA U.S.-MexicoBorderlands ViewBorderlands View

of the Edwards-Trinityof the Edwards-TrinityAquiferAquifer

ByRadu BoghiciTexas Water

Development Board

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35

COAHUILA

TAMAULIPAS

NUEVO LEON

SAN ANTONIO

LAREDO

ST. HEDWIG

ALICE

DEL RIO

KERRVILLE

SEGUIN

NEW BRAUNFELS

HONDO

AUSTIN

EDINBURG

UVALDE

FREER

POTHPLEASANTON

RIO GRANDE CITY

DEVINE

PEARSALL

EAGLE PASS

BOERNE

SONORA

CRYSTAL CITY

COTULLA

JUNCTION

FALFURRIAS

BRACKETTVILLE

FREDERICKSBURG

ASHERTON

LEAKEY

WEBB

VAL VERDE

DUVAL

FRIO

TERRELL

EDWARDSKERR

UVALDE

DIMMIT

KINNEY

BEXAR

STARR

MEDINA

ZAVALA

LA SALLE

SUTTON

ZAPATA

REAL

KIMBLE

MAVERICK

JIM HOGG

HIDALGO

ATASCOSA

LIVE OAK

BROOKS

McMULLEN

HAYS

GILLESPIE

WILSON

BLANCO

CROCKETT

BANDERACOMAL

JIM WELLS

KENDALL

PECOS TRAVIS

GUADALUPE

KARNES

BREWSTER

WILLIAMSON

NAVA

MIER

PALAUCLOETE

OCAMPO

SABINAS

MORELOS

JIMENEZ

HIDALGO

CANDELA

ALLENDE

ANAHUAC

ZARAGOZA

MONCLOVA

LAMADRID

FRONTERA

CASTAÑOS

NADADORES

RIO BRAVO

SACRAMENTO

SAN CARLOS

BUSTAMANTE

AGUALEGUAS

VILLA UNION

ALAMOS, LOS

GUERRA, LOS

NUEVA ROSITA

CIUDAD ACUÑA

NUEVO LAREDO

OCHO DE ENERO

PIEDRAS NEGRAS

CIUDAD CAMARGO

ESPERANZAS, LAS

PRIMERO DE MAYO

SAN JOSE DE AURA

SAN JUAN DE SABINAS

MINAS DE BARROTERAN

LAMPAZOS DE NARANJO

CIUDAD DE VILLALDAMA

CIUDAD MIGUEL ALEMAN

NUEVA CIUDAD GUERRERO

CIUDAD MELCHOR MUZQUIZ

CIUDAD SABINAS HIDALGO

CUATROCIENEGAS DE CARRANZA

COLONIA VENUSTIANO CARRANZA

MINAS LA FLORIDA (FLORIDA, LA)

Location Map

0 50 100 15025Kilometers

±

AQUIFERS WITHIN STUDY AREA

EA

SX

TT E R

AW

M

ENT

POLEDEV

BO

AR

D

LegendCities

Study Area Boundary

Carrizo-Wilcox aquifer (outcrop)

Carrizo-Wilcox aquifer (downdip)

Allende-Piedras Negras Valley aquifer

Edwards-Trinity aquifer system (outcrop)

Edwards-Trinity aquifer system (downdip)

Area of Interest

Map prepared by Mark HayesTexas Water Development Board

April 30, 2002

TEXAS

MEXICO

#Y

#Y

#Y

#Y

#Y

#Y#Y

#Y

#Y

#YAllende

El Remolino

Las Albercas

Uvalde

Del Rio

Camp Wood

BracketvilleRio Grande

Nueces River

West N

ue ces Riv er

Devi

ls Ri

ver

East F

ork

Sycam

ore C

reek

Dry Fr io R

i ver

Leona Ri ver

Evans Creek

Red Bluff C

reek

Pinto

Cre e

k

Dry Devi

ls Rive

r

Indian C ree k

Pulliam Creek

Las M

oras C

reek

Frio River

Elm

Cre

ek

P eco

s Riv

er

Dol

an C

reek

Deadmans

Canyon

Indi

an C

r eek

La Zorra

Las Vacas

San Rodr igo

Los Arboles

El Oregano

La Vaca

La Pari

da

El B

obo

El Caballo

Los Alamos

La Ventana

Canal General

San Diego

Las Cuevas

San Antonio

Ri o

Es c

ondi

do

Cd. Acuna

The "Bad Water Line" (TDS = 1,000 mg/l)

Study area boundary

20 0 20 40 KilometersS

N

EW

Edwards-Trinity aquifer

DowndipOutcrop

International Amistad Reservoir#Y Cities and towns

Surface water courses

Location Map

Correlation Diagram

ERATHEM

CENOZOIC

ME

SO

ZO

IC

SYSTEM

Quaternary

Tertiary

GROUP UNITED STATES MEXICO

DEVILS RIVERTREND

MAVERICKBASIN

PALE

OZO

IC

Uvalde Gravel

SERIES

CR

ETAC

EO

US

GULFIAN

CO

MAN

CH

EAN

Anacacho Limestone

PERMIAN

Rocks of Ouachita Structural Belt

Dev

ilsR

iver

Form

atio

n Salmon Peak Formation

McKnight Formation

West Nueces Formation

WashitaGroup

FredericksburgGroup

TrinityGroup

Basal

Cretaceous

Sand

Maxon Sand

Pearsall Fm.

Hosston Formation

Sligo Fm.

Undivided

CambrianthroughPennsylvanian

Alluvium

Sabinas ConglomerateTaylor & Navarro Groups

Austin GroupEagle Ford GroupBuda Limestone

Del Rio Clay

Cupido Formation

La Pena Formation

Glen Rose Limestone

EXPLANATION

Edwards-Trinity aquifer system

Allende - Piedras Negras Valley aquifer

Cretaceous rocks not part of Edwards-Trinityaquifer system because they are discontinuous,unsaturated, or have low permeability

Modified from Barker et al., 1994, table 1

Geologic Province Areas

Distribution of Transmissivityand Well Yields


N

EW

# 4 - 16# 0.5 - 4

# 16 - 50# 50 - 80# 80 - 400

COAHUILAWell Yields (l/s)

TEXASTransmissivity (m2/day)

# < 20,00020,000 - 40,000#

# 40,000 - 60,000# 60,000 - 80,000# > 80,000

Transmissivity values estimated from specific capacity tests.Sources of information: TWDB groundwater database and CILA.

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El Remolino

Cd. Acuna

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Del Rio

Potentiometric Surface Map

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366338

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424560

656

715

Rio Grande

Nueces River

West Nueces River

Dev

ils R

iver

East

Fork

Syca

more Cree

k

Dry Fri o R iver

Le ona Rive r

Evans Creek

Red Bluff Creek

Pinto

Cre

ek

Dry Devils River

Ind ian Creek

Pulliam Creek

Las M

oras C

reek

Frio River

E lm

Cre

e k

Peco

s Riv

e r

Dol

an C

reek

Deadmans C

anyon

India

n Cree

k

700

600500

350

300

450

450

400

400

450

400

350

500

450

Dry Devils River

320500

350

400

540

450

400

300350

365

La Zorra

Rio S eco

San Diego

Canal

General

Los Alamos

El Caballo

El B

obo

La Par

ida

La Vaca

El Oregano

Los Arboles

San RodrigoLas Vacas

Rio Grande309

Allende

El Remolino

Cd. Acuna

Las Albercas

Uvalde

Del Rio

Camp Wood

Brackettville

#350 Water-level elevation in well

(meters above sea level)

Surface streams

Line of equal hydraulic head (meters above sea level)350


Sources of data: TWDB, INEGI10 0 10 20 KilometersS

N

EW

Del Rio

Uvalde

Well Hydrographs

#Y

#Y#Y

#Y

#Y

#Y

#Y

#Y

#Y

#Y

Allende

El Remolino

Cd. Acuna

Las Albercas

Uvalde

Del Rio

Camp Wood

Bracketville

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N

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10 0 10 20

Km

Distribution of �2H, �18O, 14C,�13C, and 3H

Plot of Plot of ��22H versus H versus ��1818O ForO ForEdwards-Trinity SamplesEdwards-Trinity Samples

-38

-36

-34

-32

-30

-28

-6 -5.5 -5 -4.5 -4

�2 H

o/o

o SM

OW

�18O o/oo SMOW

GMWL

R2 = 0.89S = 4.97

71-15-401

55-63-702

70-45-505

50-44-801

70-29-101

70-41-301

Groundwater Pumpage Fromthe Edwards-Trinity Aquifer,

1980-1997

0

50

100

150

200

250

1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997

Year

Gro

undw

ater

Pum

page

(hm3 )

IndustrialLivestockMunicipalIrrigationTotal

-0.68

1.94 -0.75 -0.48

-1.65

0.22

0.14

2.56

-1.60

-2.50

0.43

2.68

-1.00

-1.18

-0.17

-1.80

1.41

0.311.12 Palmer Index

Hydrochemical Facies of theEdwards-Trinity Aquifer

#Y

#Y#Y

#Y

#Y

#Y

#Y

#Y

#Y

#Y

Uvalde

Del Rio

Camp Wood

Brackettville

Allende

El Remolino

Cd. Acuna

Las Albercas

Rio Grande

Nueces River

Wes t Nu ece s Ri ver

De v

il s R

iver

Eas t Fo rk

Syca

more C

reek

Dry Fr io R

ive r

L eo n

a R i

ver

Red Bluff Creek

Pin t

o C r

eek

Pulliam CreekD

olan

Cree

k

India

n Cree

k

La Zorra Las VacasLos Arboles

El Oregano

La Vaca

El B

obo

El Caballo

Los Alamos

La Ventana

Rio SecoLas Cuevas

San Antonio


N

EW

Edwards-Trinity aquiferSurface streams

Total dissolved solids (TDS)

TDS < 1,000 mg/l1,000 < TDS < 3,000 mg/l

Sources of data: TWDB, INEGI, CFE.

Sulfate Distribution Map

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Las Albercas

Uvalde

Del Rio

Camp Wood

Brackettville

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N

EW



Surface streams

Sulfate concentration# < 250 mg/l# > 250 mg/l

Nitrate Distribution Map

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El Remolino

Cd. Acuna

Uvalde

Del Rio

Camp Wood

Brackettville

5.35.35.3 5.3

5.35.3

8.4

0.0 5.35.3

0.00.00.0 0.00.05.3 0.0

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9.49.8

8.58.9

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7.48.7

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9.39.7

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7.75.5

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5.88.5

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2.42.5

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5.3


Edwards-Trinity aquiferSurface streams

Nitrate Concentrations# NO3 < 44.3 mg/l# NO3 > 44.3 mg/l


N

EW

Edwards-Trinity GAM Stakeholders Advisory Forum 4June 25, 2002 – Ozona, Texas

List of Attendees

Name AffiliationWendell Moody Private CitizenScott Holland Sterling County UWCD / Irion County Water Conservation DistrictGrant Snyder URS CorporationAlyson McDonald Texas Coop. ExtensionStan Reinhard Hickory UWCD NO. 1Johnny Jones Crockett CountyJanet Adams Jeff Davis County UWCDRoy Walston Crockett CountyWill Wilde City of San AngeloCindy Cawley Plateau UWCDAllan Lange Lipan-Kickapoo Water Conservation DistrictDennis Clark Emerald UWCDJoe David Ross Private CitizenLarry Hoffmann Private CitizenRoberto Anaya Texas Water Development BoardRadu Boghici Texas Water Development BoardRick Harston Glasscock County UWCDCindy Weatherby Santa Rita UWCDCameron Cornett Headwaters UWCD

Edwards-Trinity GAM Stakeholders Advisory Forum 4June 25, 2002 – Ozona, Texas

Meeting Summary

About 19 people attended the fourth Edwards-Trinity Aquifer Groundwater AvailabilityModeling Stakeholders Advisory Forum, held in Ozona, Texas. The stakeholders presentwere representing 9 local groundwater conservation districts, 2 consulting firms, andlocal landowners.

As a guest speaker, Radu Boghici of the Texas Water Development Board presented hisfindings on his recently completed US-Mexico Borderlands study. He discussed thehydrogeologic relationship between Edwards-Trinity aquifer units on both sides of theUS-Mexico border. Roberto Anaya presented an update on the pre-developmentgroundwater level conditions and the characterization of surface water features to be usedin the Edwards-Trinity model. Roberto Anaya also discussed how and why the revisedconceptual model of the Edwards-Trinity aquifer model will include the Hill Countryportion of the Trinity aquifer in addition to the Pecos Alluvium aquifer in order tofacilitate boundary condition issues. An update was also presented on the currentstructural geometry of the model layers and the size and orientation of the model grid tobe used. The session ended with an update on the pumping tests and hydraulic propertiesfor the Edwards-Trinity. The stakeholders were notified that the modeling project is stillslightly behind schedule and that additional staff is assigned and working hard to bringthe project back on schedule.

The next SAF meeting was tentatively scheduled for the third Thursday in October 2002in Big Lake, Texas. Potential topics for the next forum include 1) final structure and 3-Dmodel grid with associated boundary conditions; 2) final distribution of hydraulicproperties; and 3) status and methodology for distributing pumpage, recharge, andevapotranspiration; 4) a discussion on methods to be used for steady-state modelcalibration.

Primary Stakeholder Issues Follow:

1) A stakeholder suggested that spring information could be used to improve pre-development water level surfaces.

ANSWER: The suggestion was well taken and will be investigated and implementedwhere possible.

2) A stakeholder suggested contacting the TNRCC for surface water data that they collectfor special projects.

ANSWER: The suggestion was well taken and the TNRCC will be contacted andsolicited for any available surface water data within the Edwards-Trinity study area.

3) A stakeholder asked how the down-dip boundary would be handled in the confinedportions of the aquifer in Kinney and Val Verde counties.

ANSWER: The down-dip boundary will be treated in the same way as the method beingused by the Edwards BFZ model. USGS will be contacted to see if the 3,000 mg/L or10,000 mg/L TDS boundary is being used.

4) A stakeholder is concerned that the model will be used to misrepresent the“availability” of groundwater. He states that just because the water levels show that thereis water in the aquifer it does not mean that that water can be readily produced.

ANSWER: The model will be well documented with assumptions and limitations on boththe development of the model and the use of the model.

5) A stakeholder still has concerns that the model does not include faults that he has beeninformed of by local oil patch workers near his property in Sutton County.

ANSWER: It was explained that significant faults may exist within the older Paleozoicrocks beneath the Cretaceous Edwards-Trinity aquifer sediments but that these faults donot propagate up into the younger Cretaceous rocks. The difference between faults andfractures was also explained and though small faults may exist within the Edwards-Trinity rocks, they are too small to show up in the model’s structural geometry.

6) A stakeholder believes that not enough money and effort is being spent to “accurately”determine recharge rates to the aquifer and asked what method is best to determinerecharge because all the experts seem to come up with a different rate.

ANSWER: Agreeably and unfortunately recharge rates are not an easy parameter toestimate. Recharge rates are dependent upon many factors and vary over both time andspace. Current technology and data do not allow for “accurate” measurement of recharge.The Edwards-Trinity model will produce the best available estimates of recharge ratesonce the model has been calibrated.

7) A stakeholder asked why the model grid was extended so far to the south-west.

ANSWER: The model grid was extended to incorporate portions of the Edwards-Trinityon the Mexico side of the Rio Grande at some point in the future when more data isavailable. It also allows for a portion of the Edwards-Trinity within the eastern Big Bendregion of Brewster County where the geology is too complex to be modeled in the currentproject. At some point in the future when better knowledge and data of that area becomesavailable it may be added to the model.

-Roberto Anaya, 06/27/02

Welcome To The Fourth Stakeholders Advisory Forum€¦ · In The Edwards-Trinity (Plateau) Aquifer...

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