1. Current State of
Management in Texas
Larry French, P.G.
Director, Groundwater Resources
Texas Water Development Board
Presented at the Texas Groundwater Summit
August 28, 2012

2. 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
of subsidence in a groundwater management
area.”
(in context of proposing desired future
conditions)

3. Keep in mind…this is what is
being managed.

4. Data – the “blocking and tackling” of
groundwater management
• Needed to make appropriate management
decisions.
• What is the effect of management on the
resource?

7. The Groundwater
Management “Equation”
GCDs GMAs DFCs TWDB MAGs
RWPG

8. What is Groundwater Availability?
Groundwater
Policy Science
Availability
Desired GAM Modeled
Future or other Available
Conditions tool Groundwater
Goal: informed decision-making

9. GCDs GMAs DFCs TWDB MAGs
RWPG

10. 99
GCDs

11. How is groundwater managed?
• Permitting
– Well spacing
– Production limits
• Desired future conditions
• Modeled available groundwater

12. GCDs GMAs DFCs TWDB MAGs
RWPG

13. 16
GMAs

14. GCDs GMAs DFCs TWDB MAGs
RWPG

15. 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.
• For “relevant” aquifers
• Broad Policy Goal
– Drawdown (most DFCs)
– Spring flow (a few DFCs)
– Storage volumes (High Plains)
• Updated at least every 5 years

16. 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:
– 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

17. Example:
Non Relevant Major Aquifers in Region F

18. DFC Balancing
• Highest practicable level of • Conservation, preservation,
groundwater production protection, recharging and
prevention of waste of
groundwater and control of
subsidence

19. GCDs GMAs DFCs TWDB MAGs
RWPG

20. Groundwater Availability Models
(GAMs)
• Approximations of reality
• Objective of models: define groundwater
availability
– Groundwater district management plans
– Regional water planning group plans

21. 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 DFC
Example:
100,000 acre-feet per year

22. GCDs GMAs DFCs TWDB MAGs
RWPG

24. Districts in GMAs
decide Desired Future Conditions
and deliver to TWDB
TWDB provides estimates
of Modeled Available Groundwater
to districts and regions
Districts and regions include
Modeled Available Groundwater
in plans

25. 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 areas
• GAMs – the next generation
• DFCs – the next round underway (petitions
have been resolved….but there is a lawsuit)

26. Management Challenges
• Brackish groundwater development
• Energy development (fracing)
• Legal dynamics and uncertainties

27. Larry French, P.G.
Director, Groundwater Resources
larry.french@twdb.texas.gov
512-463-5067