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Current State of
Management in TexasLarry French, P.G.
Director, Groundwater Resources
Texas Water Development Board
Presented at the Texas Groundwater Summit
August 28, 2012
Management in Texas
Groundwater Management
From law (TWC §36.108 (d-2)), “…a balance between the highest practicable level of groundwater production and the conservation, preservation, protection, recharging, and prevention of waste of groundwater and control prevention of waste of groundwater and control of subsidence in a groundwater management area.”
(in context of proposing desired future conditions)
Keep in mind…this is what is
being managed.
Data – the “blocking and tackling” of
groundwater management
• Needed to make appropriate management
decisions.
• What is the effect of management on the
resource?resource?
The Groundwater
Management “Equation”
GCDs GMAs DFCs TWDB MAGs
RWPG
What is Groundwater Availability?
SciencePolicyGroundwater
Availability
GAM
or other
tool
Desired
Future
Conditions
Modeled
Available
Groundwater
Goal: informed decision-making
GCDs GMAs DFCs TWDB MAGs
RWPG
99
GCDs
How is groundwater managed?
• Permitting
– Well spacing
– Production limits
Desired future conditions• Desired future conditions
• Modeled available groundwater
GCDs GMAs DFCs TWDB MAGs
RWPG
16
GMAs
GCDs GMAs DFCs TWDB MAGs
RWPG
Desired Future Condition
• The desired, quantified condition of groundwater resources (such as water levels, water quality, spring flows, or volumes) at a specified time or times in the future or in perpetuity. times in the future or in perpetuity.
• For “relevant” aquifers
• Broad Policy Goal– Drawdown (most DFCs)
– Spring flow (a few DFCs)
– Storage volumes (High Plains)
• Updated at least every 5 years
In general, what are relevant* and
non-relevant* aquifers?
• Relevant:
– Major (9) and minor (21) aquifers defined by TWDB*
– Any other aquifer where groundwater production is now or expected to be managed by GCD (i.e., permitted)
• Non-Relevant:• Non-Relevant:
– No large-scale production anticipated
– Production will not affect conditions in relevant aquifer(s)
– Look at proposed definition in draft TAC Chapter 356 rules
*Fine print caution: these statements are “common practice” but not legally defined in statute or current rule
Example:
Non Relevant Major Aquifers in Region F
DFC Balancing
• Highest practicable level of
groundwater production
• Conservation, preservation,
protection, recharging and
prevention of waste of
groundwater and control of
subsidence
GCDs GMAs DFCs TWDB MAGs
RWPG
Groundwater Availability Models
(GAMs)• Approximations of reality
• Objective of models: define groundwater • Objective of models: define groundwater
availability
– Groundwater district management plans
– Regional water planning group plans
Modeled Available Groundwater (MAG)
• GCDs, 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 DFCproduction will achieve an applicable DFC
Example:
100,000 acre-feet per year
GCDs GMAs DFCs TWDB MAGs
RWPG
Districts in GMAs
decide Desired Future Conditions
and deliver to TWDB
TWDB provides estimates
of Modeled Available Groundwaterof Modeled Available Groundwater
to districts and regions
Districts and regions include
Modeled Available Groundwater
in plans
What’s new/next in groundwater
management?
• Data based – continued measurements and
improved accessibility of the data (WIID)
• Issues with non-relevant aquifers and deciding
on the groundwater availability in these areason the groundwater availability in these areas
• GAMs – the next generation
• DFCs – the next round underway (petitions
have been resolved….but there is a lawsuit)
Management Challenges
• Brackish groundwater development
• Energy development (fracing)
• Legal dynamics and uncertainties