evaluating mags & pumping, dfcs and waterl levels: preparing for round 2 of joint groundwater...

Prairielands GCD

Evaluating MAGs & Pumping, DFCs & Water Levels

Preparing for Round 2 of Joint Groundwater Planning

Josh Grimes, GM of PGCDJames Beach, PG

Prairielands GCDPrairielands GCD

Prairielands GCD

• Formed in 2009

• Fee based district

• Online registration, reporting, and payment

• Financially supporting the Update of NTGAM• Not meaningfully involved in Initial Round of

Joint Groundwater Planning (DFCs)


Background

• Prairielands was assigned DFCs for 5 aquifers in 4 counties

• DFCs were defined as feet of water level decline in 2060

Prairielands GCD

Cross-Section (Updated BEG Structure)

Hensel


Comparing Pumping and MAGs

1. Estimate formations screened for both exempt and non-exempt wells

2. Proportion pumping

3. Move all pumping to a MAG formation

Prairielands GCD

Exempt Well Evaluation

Prairielands GCD

Above Woodbine Woodbine

Fredericksburg/Washita Paluxy

Glen Rose Hensel Pearsall Hosston

Below Hosston

Grand Total

Ellis 45 118 8 7 178Domestic 11 72 6 89

Geothermal 18 18Industrial 1 5 1 7Injection 5 5Irrigation 6 20 26

Public Supply 7 1 5 13Stock 3 14 17

(blank) 1 1 1 3Hill 12 55 40 41 11 7 1 28 195

Domestic 9 41 23 23 3 2 4 105Geothermal 1 1 5 7

Industrial 2 2Injection 4 4Irrigation 1 8 3 3 15

Public Supply 4 4Stock 1 1 1 1 1 5

(blank) 2 4 14 8 5 1 19 53Johnson 3 241 254 295 76 99 2 179 3 1152

De-watering 2 1 3Domestic 1 127 150 229 50 11 23 591

Geothermal 2 17 19Industrial 4 9 6 3 1 9 32Injection 1 4 1 6Irrigation 78 49 11 1 4 17 1 161

Public Supply 1 2 11 2 7 23Stock 15 15 7 3 2 42

(blank) 2 17 11 27 16 79 1 120 2 275Somervell 15 30 171 5 177 9 407

De-watering 1 1Domestic 12 28 152 5 159 7 363Industrial 3 1 4Injection 1 1Irrigation 1 1 3 2 1 8

Public Supply 4 3 7Stock 1 7 8

(blank) 1 11 3 15Grand Total 60 414 302 351 117 277 8 391 12 1932

TDLR Driller’s Logs

2001-2013

Well Count by Aquifer and Use

BEG Structure

Prairielands GCD

COMPARISON OF DISTRICT METER DATA AND MAGS

Prairielands GCD


Big Picture Comparison

• Meter data show yearly variation in pumping

• Explained by drought other factors

• Need to look at long term trends

• Pumping generally less than MAGs on County basis

Prairielands GCD

MORE DETAILED COMPARISON BY AQUIFER


Detailed Comparison

• Hosston Aquifer production exceeds MAGs in 3 of 4 counties

• Hensel and Glen Rose also exceed MAG in 2 counties

Prairielands GCD

COMPARISON OF DFCS ANDWATER LEVEL CHANGES

Prairielands GCD

Prairielands GCD

DFCs by county and aquifer


Findings from Historical Data

• Limited wells and measurements from TWDB database to assess 19 DFCs

• Short term data and long term data can result in different trends

• Need to use long-term trends (10-20 years)• Need more wells and more measurements

Prairielands GCD

Available Data

Prairielands GCD

Comparison of DFC andwater level decline

Fine Print1. Preliminary data and analysis2. Based on arithmetic averages of wells by county3. Summary based on limited information4. Evaluation not meant to imply any particular regulatory response

Aquifer / County

Woodbine Paluxy Glen Rose Hensel Hosston

Ellis Less than DFC No Data No Data No Data Less than DFC

Hill exceeds DFCOld data only (1941-1991)

No Data Less than DFC exceeds DFC

Johnson exceeds DFC exceeds DFC Less than DFC No Data Less than DFC

Somervell NO DFC Less than DFCOld data only (1950-1986)

exceeds DFC Less than DFC

Prairielands GCD

Agreement between MAG and DFC?

Aquifer / County

Woodbine Paluxy Glen Rose Hensel Hosston

Ellis Agree No Data No Data No Data Disagree

Hill Disagree No Data No Data Agree Agree

Johnson Disagree Disagree Disagree No Data Disagree

Somervell NO DFC Agree No Data Agree Agree

AgreeWater level decline > DFC and Pumping > MAG

ORWater level decline < DFC and Pumping < MAG

DisagreeWater level decline > DFC and Pumping < MAG

orWater level decline < DFC and Pumping > MAG


Summary

• Pumping data from meters is helpful to compare to estimated MAGS

• 19 DFCs require a significant number of monitoring wells

• County/aquifer “disagreements” need a closer look, more data, better data, better model, etc.

• Prairielands GCD:– developing and improving monitoring network – improving meter data– supporting GAM update– Focusing on long-term goals

evaluating mags & pumping, dfcs and waterl levels: preparing for round 2 of joint groundwater...

Technology

mags prairielands gcd

aquifer prairielands

pgprairielands gcd

measurementsprairielands

countiesprairielands

aquiferprairielands

structureprairielands

evaluationprairielands