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Desired Future Conditionsand other joint planning matters
Texas Alliance of Groundwater DistrictsLeadership TrainingNovember 6, 2017
Fort Stockton, Texas
Robert G. Bradley, P.G., C.T.C.MGroundwater Technical Assistance
1
Desired Future Conditionsand other joint planning matters
Texas Alliance of Groundwater DistrictsLeadership TrainingNovember 6, 2017
Fort Stockton, Texas
Robert G. Bradley, P.G., C.T.C.MGroundwater Technical Assistance
2
The following presentation is based upon professional research and analysis within the scope of the Texas Water Development Board’s statutory responsibilities and priorities but, unless specifically noted, does not necessarily reflect official Board positions or decisions.
Preview
• What is a groundwater management area?
• What is groundwater joint planning?
• What are desired future conditions?
– How are they developed?
– Why are they important?
– How are they used?
Major Aquifers
Minor Aquifers
Minor AquifersCross Timbers Aquifer(proposed)
GroundwaterManagement
Areas
Groundwater Joint Planning
• Forward copy of new or revised management plan to districts in the groundwater management area
• District Representatives meet annually to– Conduct joint planning
– Review management plans and accomplishments
– Proposals to adopt new or amend DFCs
• Management plan review – consideration of the goals
– Effectiveness of measures
– any other matters
– degree to which each management plan achieves the DFCs
Groundwater
Availability
prior to 1997
Old School
Groundwater
Availability
20+ years ago
What is Groundwater Availability?
SciencePolicyGroundwater
Availability
GAM or other
tool
DesiredFuture
Conditions
Modeled Available
Groundwater
Goal: informed decision-making
Desired Future Condition
• The desired, quantified condition of groundwater resources– water levels, water quality, spring flows, or volumes) – at a specified time or times in the future or in perpetuity.
• For “relevant” aquifers (Major and Minor aquifers)• Broad Policy Goal
– Drawdown (most)– Spring flow (a few)– Storage volumes (High Plains, Llano Uplift)
• Updated at least every 5 years (propose by May 1, 2021, final adoption by January 5, 2022)
The “Factors”
• Uses & conditions
• State water plan
• Hydrologic conditions
• Environmental impacts
• Land subsidence
• Socioeconomics
• Property rights
• Feasibility
• Anything else
Shameless Plug
The vulnerability of each major and minor aquifer in Texas to subsidence
• Research of Contract with LRE Water, LLC, TWDB Contract No. 1648302062
• Provide tool to assess risk and monitoring suggestions for groundwater conservation districts with high risk
• Covers the entire state – (except Subsidence Districts)
• Final report due March 30, 2018
A balancing act
• Highest practicable level of groundwater production
• Conservation
• Preservation
• Protection
• Recharging
• Prevention of waste
• Control of subsidence
productionconservationand friends
Meet and review groundwater
conditions
Vote to propose desired future
conditions
Comment period and public hearings
Vote to adopt desired future
conditions
Adopt desired future conditions
Receives desired future conditions and explanatory
report
DESIRED FUTURE CONDITIONS: PROCESS TO ADOPT
District representatives in groundwater
management area
Individual districts
Texas Water Development Board
Not later than May 1, 2021
Not later than January 5, 2022
Examples
• GMA 1 – volume
• GMA 8 – spring flow
• GMA 15 – drawdown
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50%
80%
40%
Percent of volume in storage remaining in 50 years for the period 2012-2062.
20’Approximately 20 feet of total average drawdown in 50 years for the period 2012-2062.23-27’
Maintain at least 100 acre-feet per month of stream/spring flow in Salado Creek during a repeat of the drought of record in Bell County.
Maintain at least 42 acre-feet per month of aggregated stream/spring flow during a repeat of the drought of record in Travis County.
Maintain at least 60 acre-feet per month of aggregated stream/spring flow during a repeat of the drought of record in Williamson County.
The Desired Future Condition for the counties in the management area shall not exceed an average drawdown of 13 feet for the Gulf Coast Aquifer System at December 2069.
County Aquifer DFC
Colorado Chicot and Evangeline Aquifers 17
Colorado Jasper Aquifer 23
Matagorda Chicot and Evangeline Aquifers 11
Wharton Chicot and Evangeline Aquifers 15
County Aquifer DFCAransas Gulf Coast Aquifer System 0Bee Gulf Coast Aquifer System 7Calhoun Gulf Coast Aquifer System 5Dewitt Gulf Coast Aquifer System 17Fayette Gulf Coast Aquifer System 16Goliad Gulf Coast Aquifer System 10Jackson Gulf Coast Aquifer System 15Karnes Gulf Coast Aquifer System 22Lavaca Gulf Coast Aquifer System 18Refugio Gulf Coast Aquifer System 5Victoria Gulf Coast Aquifer System 5
Total Estimated Recoverable Storage
• Texas Administrative Code Rule §356.10– The estimated amount of groundwater within an
aquifer that accounts for recovery scenarios that range between 25 percent and 75 percent of the porosity-adjusted aquifer volume.
• Caution:– It is only a volume of water without considering
any consequences of withdrawing it (including subsidence, economics, water quality, or other impacts.)
Modeled Available Groundwater
• Modeled available groundwater represents the total amount of groundwater, including both permitted and exempt uses, that can be produced from the aquifer in an average year, that achieves a “desired future condition.”
• It is expressed as a rate – generally in acre-feet per year.
Some facts about modeled available groundwater…
Modeled Available Groundwater and Permits (1 of 2)
• The amount of water may be produced on an average annual basis to achieve a desired future condition.
• Districts, to the extent possible, shall issue permits up to the point that the total volume of exempt and permitted groundwater production will achieve an applicable desired future condition.
• But also….not so simple! (next page)
Modeled Available Groundwater and Permits (2 of 2)
• The district shall manage total groundwater production on a long-term basis to achieve an applicable desired future condition and consider:
– Modeled available groundwater
– Groundwater produced under exempt uses
– Amount of groundwater previously permitted
– Estimate of permitted groundwater that is actually produced
– Yearly rainfall and groundwater production patterns.
Before desired future conditions…
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Now, a desired future condition…
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Groundwater development meets a desired future condition.
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TWDB groundwater data
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Three points to consider:
1. Desired future conditions are an expression of local groundwater management.
2. Desired future conditions can be modified by districts to address improvements in data/science/technology and changing groundwater usage.
3. Districts are responsible for managing the groundwater resource to achieve the desired future condition
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Other items to consider:
• Appealing the reasonableness of the DFCs is done to the individual districts.
– The district contracts with SOAH to hold hearing
– TWDB prepares • Administrative review
• Scientific study
• TCEQ inquiry
– Failure to participate in joint planning
– Failure to adopt applicable DFCs
– Failure to update management plan by 2nd
anniversary of DFC adoption
– Rules are not designed to achieve DFC
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