Bill Hutchison, PhD. P.E., P.G.

1. GMAs 2, 3, 7, 11, and 13
Summary of Joint Planning To Date
Bill Hutchison, Ph.D., P.E., P.G.
TAGD Meeting
May 19, 2016

2. GMA 2
• 7 GCDs
• 5 Aquifers
• Key Factors: Property Rights, Socioeconomic Effects
• Key Issue: Future reductions in Ogallala pumping rates
• New GAM provided quantitative insight
• Ogallala DFC is focused on physics and economics
• Avoids equal outcome basis of 50/50
• Emphasizes aquifer variation and hydraulics of pumping in an
aquifer with declining saturated thickness
• Range is provided (wet years and dry years)

3. GMA 3
• 2 GCDs
• 7 Aquifers
• Key Issue: Recently Completed GAMs
• Late start
• Changes from aquifer analyses that were basis for first
DFCs
• Overlap with GMA 7 for most aquifers

4. GMA 7
• 21 GCDs
• 14 Aquifers
• Key Factor: Surface Water Impacts (eastern portion)
• Key Issue: Recently Completed GAMs
• Late start
• Changes from aquifer analyses that were basis for first
DFCs
• Val Verde County
• No GCD (relevant or not relevant)
• Impacts of potential future pumping outside of GMA 7
(surface water)

5. GMA 11
• 4 GCDs
• 7 Aquifers
• Key Factor: Regional Water Plan Strategies
• Presentations to Region D and Region I in May (part of outreach to non-
GCD counties)
• Key Issue: GAM Limitations
• Unable to update model calibration period (1975-1999)
• Rising groundwater levels in outcrop area
• Model update should be available for next round
• DFC for Sparta/Queen City/Carrizo-Wilcox
• DFC in some counties does not match model output for outcrop
drawdown
• MAG will fully support all recommended and alternative Region D
and Region I strategies in 2016 plan

6. GMA 13
• 9 GCDs
• 7 Aquifers
• Key Factor: Regional Water Plan Strategies
• Stakeholders provided about $10,000 in funding
• Key Issue: GAM Limitations
• Over prediction of drawdown in outcrop area
• DFC for Sparta/Queen City/Carrizo-Wilcox
• Outcrop area based (focused on impacts to shallow wells and
surface water)
• DFC does not match model output for outcrop drawdown
• MAG will fully support all recommended and alternative
Region L strategies in 2016 plan

7. GMA GMA 2 GMA 3 GMA 7 GMA 11 GMA 13
Consultant Start Year 2015 2015 2014 2015 2012
GAM Runs 17 29 35 7 51
Tech Memos 6 6 9 7 9
GMA Costs $39,000 $17,000 $55,000 $34,000 $62,000
Supplemental Costs (GCD) $7,000 $0 $0 $2,000 $3,000
Summary Statistics

8. Questions and Discussion
Bill Hutchison, Ph.D., P.E., P.G.
billhutch@texasgw.com