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Cypress Creek Project and Cypress Creek Project and the Desired Future the Desired Future Conditions Process Conditions Process Negotiating the Bumps at the Negotiating the Bumps at the Intersection of Science Intersection of Science and Public Policy and Public Policy Douglas A. Wierman, P.G., Hays Trinity GCD Douglas A. Wierman, P.G., Hays Trinity GCD October 1, 2009 October 1, 2009

Desired Future Condition (DFC) Presentation

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Presentation for the Desired Future Condition Process for Groundwater Management Area 9 – Trinity Aquifer

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Page 1: Desired Future Condition (DFC) Presentation

Cypress Creek Project and the Cypress Creek Project and the Desired Future Conditions Desired Future Conditions

ProcessProcess

Negotiating the Bumps at the Negotiating the Bumps at the Intersection of Science Intersection of Science

and Public Policyand Public Policy

Douglas A. Wierman, P.G., Hays Trinity GCDDouglas A. Wierman, P.G., Hays Trinity GCDOctober 1, 2009October 1, 2009

Page 2: Desired Future Condition (DFC) Presentation

Alphabet SoupAlphabet Soup • GMA – Groundwater Management Area GMA – Groundwater Management Area • GCD – Groundwater Conservation DistrictGCD – Groundwater Conservation District• DFC – Desired Future ConditionDFC – Desired Future Condition• MAG – Managed Available GroundwaterMAG – Managed Available Groundwater• GAM – Groundwater Availability ModelGAM – Groundwater Availability Model• TWDB – Texas Water Development TWDB – Texas Water Development

BoardBoard• DOR – Drought of RecordDOR – Drought of Record

Page 3: Desired Future Condition (DFC) Presentation

OutlineOutline of Today’s of Today’s PresentationPresentation• Overview of the DFC ProcessOverview of the DFC Process

• Hydrogeology of Jacob’s Well and Cypress Hydrogeology of Jacob’s Well and Cypress

CreekCreek

• Status of GMA #9 DFCs and MAGsStatus of GMA #9 DFCs and MAGs

• Possible DFC/MAG Implementation Possible DFC/MAG Implementation Strategies in HTGCDStrategies in HTGCD

Page 4: Desired Future Condition (DFC) Presentation

Overview of the DFC ProcessOverview of the DFC Process• In September, 2005, House Bill 1763 of the 79th In September, 2005, House Bill 1763 of the 79th

Texas legislature became effective. HB 1763 was Texas legislature became effective. HB 1763 was incorporated into Chapter 36 of the Texas Water incorporated into Chapter 36 of the Texas Water Code. No funding made available.Code. No funding made available.

• Groundwater planning was regionalized into Groundwater planning was regionalized into

Groundwater Management Areas (GMAs) which Groundwater Management Areas (GMAs) which consist of individual GCDs and areas not included consist of individual GCDs and areas not included in a GCD. in a GCD.

• With significant public input, GMAs must establish With significant public input, GMAs must establish a Desired Future Conditions for each aquifer in a Desired Future Conditions for each aquifer in the GMA for the period 2010 through 2060 by the GMA for the period 2010 through 2060 by September 2010.September 2010.

Page 5: Desired Future Condition (DFC) Presentation

OverviewOverview of the DFC Process of the DFC Process

• TWDB, primarily through the use of TWDB, primarily through the use of groundwater availability models, determines groundwater availability models, determines how much water can be pumped from the how much water can be pumped from the aquifer to achieve the DFC. This volume of aquifer to achieve the DFC. This volume of water is known as the Managed Available water is known as the Managed Available Groundwater, or MAG. Groundwater, or MAG.

• With public input, individual GCDs must With public input, individual GCDs must develop management strategies and rules to develop management strategies and rules to permit groundwater withdrawal up to the MAG.permit groundwater withdrawal up to the MAG.

Page 6: Desired Future Condition (DFC) Presentation

DesiredDesired Future Conditions Future Conditions• A quantitative description of a natural A quantitative description of a natural

aquifer condition/property as a goal – not aquifer condition/property as a goal – not well dischargeswell discharges

• DFCs are set for all aquifers in a GMADFCs are set for all aquifers in a GMA

• Aquifer may be subdivided Aquifer may be subdivided “geographically”“geographically”

• Approved by vote of two thirds of at least Approved by vote of two thirds of at least two-thirds of the GMA’s GCDs (In GMA #9, two-thirds of the GMA’s GCDs (In GMA #9, as few as 4 of 9 GCDs can determine DFCs as few as 4 of 9 GCDs can determine DFCs for the entire GMA)for the entire GMA)

Page 7: Desired Future Condition (DFC) Presentation

Managed Available GroundwaterManaged Available Groundwater

• Managed Available Groundwater – water that will Managed Available Groundwater – water that will be available to be available to allall end users that meets the DFC end users that meets the DFC under applicable regulatory constraintsunder applicable regulatory constraints

• MAG values are MAG values are de facto de facto “caps” and the “caps” and the mandatory basis for Regional/State Water Plansmandatory basis for Regional/State Water Plans

• Rules adopting/enforcing MAGs and supporting Rules adopting/enforcing MAGs and supporting DFCs are mandatory upon all GCDs in a GMADFCs are mandatory upon all GCDs in a GMA

Page 8: Desired Future Condition (DFC) Presentation
Page 9: Desired Future Condition (DFC) Presentation

Major and Minor Aquifers of Major and Minor Aquifers of GMA #9GMA #9

• Edwards (BFZ)Edwards (BFZ)

• Edwards-Trinity (Plateau)Edwards-Trinity (Plateau)

• Trinity – Upper, Middle and LowerTrinity – Upper, Middle and Lower

• ““Paleozoics”Paleozoics”– Ellenburger-San SabaEllenburger-San Saba– HickoryHickory– Marble FallsMarble Falls

Page 10: Desired Future Condition (DFC) Presentation

GCDsGCDs of GMA 9 of GMA 9• Bandera County River Authority And Ground Water DistrictBandera County River Authority And Ground Water District

• Barton Springs/Edwards Aquifer Conservation DistrictBarton Springs/Edwards Aquifer Conservation District

• Blanco-Blanco-PedernalesPedernales Groundwater Conservation District Groundwater Conservation District

• Cow Creek Groundwater Conservation DistrictCow Creek Groundwater Conservation District

• Edwards Aquifer AuthorityEdwards Aquifer Authority

• Hays Trinity Groundwater Conservation DistrictHays Trinity Groundwater Conservation District

• Headwaters Groundwater Conservation DistrictHeadwaters Groundwater Conservation District

• Medina County Groundwater Conservation DistrictMedina County Groundwater Conservation District

• Trinity-Glen Rose Groundwater Conservation DistrictTrinity-Glen Rose Groundwater Conservation District

• No GCD in Comal or Travis CountiesNo GCD in Comal or Travis Counties

Page 11: Desired Future Condition (DFC) Presentation

Hydrogeology of Jacob’s Well Hydrogeology of Jacob’s Well and Cypress Creekand Cypress Creek

•Hydrogeologic SettingHydrogeologic Setting

•Sources of Water to Cypress CreekSources of Water to Cypress Creek

Base Flow from Jacob’s WellBase Flow from Jacob’s Well

Storm Surge from Aquifer Storm Surge from Aquifer

Storm Water Run-offStorm Water Run-off

Page 12: Desired Future Condition (DFC) Presentation

J ac obs Well Dis c harg e

0

20

40

60

80

100

120

140

Disc

harg

e (c

fs)

J acobs WellDis charge

Page 13: Desired Future Condition (DFC) Presentation

Local Local StratigraphyStratigraphyDeveloped by A.S. Broun, District Geologist

Page 14: Desired Future Condition (DFC) Presentation
Page 15: Desired Future Condition (DFC) Presentation

Structural Cross Section B to B’ – Cypress Creek Structural Cross Section B to B’ – Cypress Creek DrainageDrainageLower Cretaceous Trinity Group, Hays County, Lower Cretaceous Trinity Group, Hays County, TexasTexas

Page 16: Desired Future Condition (DFC) Presentation

Structural Cross Section B-B’Structural Cross Section B-B’(cropped and enlarged)(cropped and enlarged)

Page 17: Desired Future Condition (DFC) Presentation
Page 18: Desired Future Condition (DFC) Presentation
Page 19: Desired Future Condition (DFC) Presentation
Page 20: Desired Future Condition (DFC) Presentation

Hydrogeology of Jacob’s Well Hydrogeology of Jacob’s Well and Cypress Creekand Cypress Creek TakeawaysTakeaways

• Base Flow from Jacob’s Well is Cypress CreekBase Flow from Jacob’s Well is Cypress Creek

• Base Flow originates in the Cow Creek Member of Base Flow originates in the Cow Creek Member of the Middle Trinity Aquifer the Middle Trinity Aquifer

• Recharge Zone is local and up dip to the westRecharge Zone is local and up dip to the west

Page 21: Desired Future Condition (DFC) Presentation

Status of GMA #9 DFCs and Status of GMA #9 DFCs and MAGsMAGs

• GAM 9 has voted and approved DFCs for GAM 9 has voted and approved DFCs for the Marble Falls, Ellenberger, Hickory and the Marble Falls, Ellenberger, Hickory and Edwards-Trinity (Plateau)Edwards-Trinity (Plateau)

• DFC for Edwards-Trinity (Plateau) set for DFC for Edwards-Trinity (Plateau) set for the preservation of stream flow in the the preservation of stream flow in the Upper Guadalupe River and it’s tributariesUpper Guadalupe River and it’s tributaries

• MAG determined for the Edwards-Trinity MAG determined for the Edwards-Trinity (Plateau)(Plateau)

• MAG has been appealedMAG has been appealed

Page 22: Desired Future Condition (DFC) Presentation

Status of GMA #9 DFCs and Status of GMA #9 DFCs and MAGsMAGs

• DFCs to be set for the Upper, Middle and DFCs to be set for the Upper, Middle and Lower TrinityLower Trinity

• TWDB has performed several GAM runs at TWDB has performed several GAM runs at the request of GMA #9 for Upper and the request of GMA #9 for Upper and Middle Trinity aquifers, not Lower Trinity Middle Trinity aquifers, not Lower Trinity AquiferAquifer

• 2000 GAM vs. 2009 GAM update2000 GAM vs. 2009 GAM update

Page 23: Desired Future Condition (DFC) Presentation

Hill County Trinity GAM Hill County Trinity GAM 2000 GAM vs. 2009 GAM2000 GAM vs. 2009 GAM

• 2000 GAM included Edwards Trinity Plateau, 2000 GAM included Edwards Trinity Plateau, Upper and Middle Trinity AquifersUpper and Middle Trinity Aquifers

• 2009 GAM update added Lower Trinity2009 GAM update added Lower Trinity

• All GAM runs to date use 2000 GAMAll GAM runs to date use 2000 GAM

• New GAM runs with 2009 GAM in processNew GAM runs with 2009 GAM in process

Page 24: Desired Future Condition (DFC) Presentation

Hays Trinity Groundwater Conservation DistrictHays Trinity Groundwater Conservation DistrictTrinity aquifer Water Budget Based on the TWDB Edwards-Trinity aquifer GAMTrinity aquifer Water Budget Based on the TWDB Edwards-Trinity aquifer GAM

(in acre-feet per year)(in acre-feet per year)

Lower Trinity aquifer – Lower Trinity aquifer – Not Included in ModelNot Included in Model•Sligo & Hosston FormationsSligo & Hosston Formations

Middle Trinity aquifer•Lower Glen Rose Formation

•Hensel Sand

•Cow Creek Limestone

PumpingPumpingSprings & Seeps

(Stream Leakage)

Springs & Seeps(Stream Leakage)

Upper Trinity aquifer•Upper Glen Rose Formation

Recharge(rainfall infiltration)

Recharge(rainfall infiltration)

Trinityaquifer

Edwardsaquifer

Lossto Edwards

Aquifer(Head Dependant Bounds)

Lossto Edwards

Aquifer(Head Dependant Bounds)

Down-gradientMovement Out

of HTGCD(Horizontal Exchange)

Down-gradientMovement Out

of HTGCD(Horizontal Exchange)

Gains toAquiferStorage

(Storage)

Gains toAquiferStorage

(Storage)

Hammett Shale (aquitard)

Page 25: Desired Future Condition (DFC) Presentation

GAM Runs HTGCD Middle GAM Runs HTGCD Middle TrinityTrinity

•Steady-State (GAM Run 08-70a)•2008 Current Pumping•GAM Run 08-20, 15-ft drawdown•GAM Run 08-70a (25% > 2008)•GAM Run 08-70b (50% > 2008)•GAM Run 08-30, variable drawdown•GAM Run 08-15, 35-ft drawdown

Page 26: Desired Future Condition (DFC) Presentation

Middle Trinity – Initial Water LevelsMiddle Trinity – Initial Water Levels

Page 27: Desired Future Condition (DFC) Presentation

Middle Trinity – 35’ Draw DownMiddle Trinity – 35’ Draw Down

Page 28: Desired Future Condition (DFC) Presentation

HTGCD 2008 Groundwater HTGCD 2008 Groundwater PumpagePumpage

Total Non-Exempt ProductionTotal Non-Exempt Production 2371 ac-ft2371 ac-ft 42%42%

Exempt Agricultural UseExempt Agricultural Use 897 ac-ft897 ac-ft 16%16%

Exempt Domestic WellsExempt Domestic Wells (330 gpd)(330 gpd) 2403 ac-ft2403 ac-ft 42%42%

TOTALTOTAL 5671 ac-ft5671 ac-ft 100%100%

Upper and Middle Trinity/Lower TrinityUpper and Middle Trinity/Lower Trinity 5385/286 ac-ft5385/286 ac-ft

Available Upper and Middle Trinity fromAvailable Upper and Middle Trinity from 3713 ac-ft3713 ac-ft

2005 HTGCD Management Plan2005 HTGCD Management Plan

Page 29: Desired Future Condition (DFC) Presentation

Hays County

0

5

10

15

20

25

30

35

40

45

0 2,000 4,000 6,000 8,000 10,000 12,000 14,000

Pumping (ac-ft/yr)

Aver

age

Draw

dow

n (ft

)*

0

2,000

4,000

6,000

8,000

10,000

12,000

14,000

Disc

harg

e (a

c-ft/y

r)

Estimated Avg Drawdown (ft) from SS Rivers & Springs (Dra in) (ac-ft/yr) BFZ (outflow; ac-ft/yr)

Rivers & Springs discharge

Balcones Fault Zone outflow

Est. Average Drawdown from Steady State

Page 30: Desired Future Condition (DFC) Presentation

Drought of record, or Drought of record, or not…not…

Page 31: Desired Future Condition (DFC) Presentation

Do we consider the DOR, or Do we consider the DOR, or do we close the DOR and do we close the DOR and just be average?just be average?

• Should we plan for average precipitation Should we plan for average precipitation or DOR? or DOR?

• Is sustainability always the best policy? Is Is sustainability always the best policy? Is it always a possible policy?it always a possible policy?

• Use of drought planning during DOR?Use of drought planning during DOR?

Page 32: Desired Future Condition (DFC) Presentation

The Real Issue The Real Issue

How does the HTGCD allocate a finite How does the HTGCD allocate a finite resource that has never been fully resource that has never been fully regulated in an environment where regulated in an environment where most feel it is their right to pump as most feel it is their right to pump as

much groundwater as they want.much groundwater as they want.

Page 33: Desired Future Condition (DFC) Presentation

SettingDFCs

DeterminingMAGs

By Aquifer

Distributing MAGs to

GCDs/Cty’s

GMADesignated

Reps

DistrictManagement

Plan 2010

District Rules & Bylaws

Implementing Policies andProcedures

TWC Chapter 36

EnablingLegislation

TWDB

GMA

Public

TWDB

GCD ProcessesJoint Regional Planning Statutes

Allowable Pumping

Page 34: Desired Future Condition (DFC) Presentation

Possible Allocation StrategiesPossible Allocation Strategies

• Management ZonesManagement Zones

– Recognize that different aquifers and geologic conditions Recognize that different aquifers and geologic conditions existexist

– Occurrence and maintenance of stream flow varies Occurrence and maintenance of stream flow varies across Districtacross District

– Recharge characteristics vary across District (age of Recharge characteristics vary across District (age of water and mining)water and mining)

Page 35: Desired Future Condition (DFC) Presentation

Possible Allocation StrategiesPossible Allocation Strategies

• Historical Use for Non-Exempt WellsHistorical Use for Non-Exempt Wells

– Water right based on some portion of past Water right based on some portion of past productionproduction

– May be permanent or short termMay be permanent or short term

– May be transferable and/or marketable to other May be transferable and/or marketable to other areas or other usesareas or other uses

Page 36: Desired Future Condition (DFC) Presentation

Possible Allocation StrategiesPossible Allocation Strategies

• Reasonable Use for Non-Exempt WellsReasonable Use for Non-Exempt Wells

– Current permitting strategy for the HTGCDCurrent permitting strategy for the HTGCD

– Permits based on a “reasonable” amount of Permits based on a “reasonable” amount of water for a specified purpose and durationwater for a specified purpose and duration

Page 37: Desired Future Condition (DFC) Presentation

Possible Allocation StrategiesPossible Allocation Strategies

• Quantifiable Property RightsQuantifiable Property Rights

– Often referred to as correlative rightOften referred to as correlative right

– Based in amount of land owned or controlledBased in amount of land owned or controlled

– May be transferable (marketable) to other areas or May be transferable (marketable) to other areas or other usesother uses

– Could include multiple aquifers beneath a propertyCould include multiple aquifers beneath a property

Page 38: Desired Future Condition (DFC) Presentation

Challenges to the HTGCDChallenges to the HTGCD

• Exempt Wells - ResidentialExempt Wells - Residential– Single family domestic use exempt up to Single family domestic use exempt up to

25,000 gpd25,000 gpd– Domestic wells can be drilled on any size lotDomestic wells can be drilled on any size lot– Current pumpage estimates rely on 330 gpd Current pumpage estimates rely on 330 gpd

that results in 42% (2403 ac-ft) of 2008 that results in 42% (2403 ac-ft) of 2008 pumpagepumpage

– Using the exempt “permitted” amount, Using the exempt “permitted” amount, domestic wells could use 182,000 ac-ftdomestic wells could use 182,000 ac-ft

Page 39: Desired Future Condition (DFC) Presentation

Challenges to the HTGCDChallenges to the HTGCD

• Exempt Wells –Agricultural WellsExempt Wells –Agricultural Wells

– Exempt from permitting and regulationExempt from permitting and regulation

– Vineyards and orchards are increasing Vineyards and orchards are increasing and expected to continue to grow and expected to continue to grow

– Currently using 16% of total productionCurrently using 16% of total production

Page 40: Desired Future Condition (DFC) Presentation

Impact of Impact of ExemptExempt Use Use GrowthGrowth

2008 GW Production

3300, 58%

2371, 42%Exempt Uses

Non-Exempt Uses

Page 41: Desired Future Condition (DFC) Presentation

Impact of Impact of ExemptExempt Use Use GrowthGrowth

2033 GW Production with 2% Annual Exempt Growth and 6000 ac-ft MAG

5700, 95%

300, 5%

Exempt

Non-Exepmt

Page 42: Desired Future Condition (DFC) Presentation

DFC Process and Cypress Creek DFC Process and Cypress Creek ProjectProject

• HTGCD needs stakeholder feedback on HTGCD needs stakeholder feedback on desired condition of Cypress Creekdesired condition of Cypress Creek

– Are aesthetics of flow the primary criteria?Are aesthetics of flow the primary criteria?– Is a Jacob’s Well management area necessary?Is a Jacob’s Well management area necessary?– What level of flow keeps creek off the 303d list?What level of flow keeps creek off the 303d list?– What is the acceptable level of risk of the creek What is the acceptable level of risk of the creek

going dry?going dry?– Is the community ready to bear the financial Is the community ready to bear the financial

cost of a low risk strategy?cost of a low risk strategy?

Page 43: Desired Future Condition (DFC) Presentation

Implementation ScheduleImplementation Schedule• DFCs/MAGs – 1Q 2010DFCs/MAGs – 1Q 2010

• Revise Management Plan – 2Q 2010Revise Management Plan – 2Q 2010

• Adopt New Rules – 3Q 2010Adopt New Rules – 3Q 2010

• Rule Implementation – 4Q 2010Rule Implementation – 4Q 2010

• GMA 9 meets at least annually to monitor progress GMA 9 meets at least annually to monitor progress towards DFCstowards DFCs

• GAM 9 revisits and may reset DFCs in five years GAM 9 revisits and may reset DFCs in five years (or less?)(or less?)

Page 44: Desired Future Condition (DFC) Presentation
Page 45: Desired Future Condition (DFC) Presentation
Page 46: Desired Future Condition (DFC) Presentation

Historical Water Level TrendsHistorical Water Level TrendsHenly Church

57-55-401

y = -0.14x + 1186

900

920

940

960

980

1000

1020

1040

1060

1080

1100

Jan

-99

Jan

-00

Jan

-01

Jan

-02

Jan

-03

Jan

-04

Jan

-05

Jan

-06

Jan

-07

Jan

-08

Month

Wat

er L

evel

Ele

vati

on

(fe

et)

Water Level

Linear Regression

30º 11' 47'' North98º 12' 45'' West

Middle Trinity Depth 460 feet

Elevation 1326 feetColorado watershed

Page 47: Desired Future Condition (DFC) Presentation

Current Thinking of HTGCDCurrent Thinking of HTGCD

• Due to the nature of the GAM, be Due to the nature of the GAM, be conservative at this timeconservative at this time

• Allow for MAG to be metered out to Allow for MAG to be metered out to account for growth of exempt wellsaccount for growth of exempt wells

• Set up groundwater management Set up groundwater management zones in critical areaszones in critical areas

• Account for DOR through drought Account for DOR through drought planningplanning

Page 48: Desired Future Condition (DFC) Presentation

Where Does GMA-9 Go From Where Does GMA-9 Go From Here?Here?

More AssessmentsMore AssessmentsMore Public InputMore Public Input

More Decision-makingMore Decision-makingMore RecommendationsMore Recommendations

Complete process in 2009Complete process in 2009