Please confirm that the GMA accepts the following assumptions for calculating modeled

Staff Report & Agenda Item Details

10. Please confirm that the GMA accepts the following assumptions for calculating modeled drawdown: 1) only include active model cells within the officialTWDB aquifer boundary- This method produces drawdown values consistent with the DFC values provided in the Explanatory Report and is consietent rvlth the methodology used in the previous planning cycle. Optionel Clarificationz (Clerical corrections to Explonatory Reportf : Edwords Group of the Edrards-Trinity (PloteauJ Aguifer; - baseline year for DFC incorrectly listed as 20OB rather than 1997 fsee Clarification #4] Ellenbvrger-San Sabo & Hickory Aquifers: - baseline year for DFC incorrectly listed as 20OB rather than 2OLO {5e€ Clarificotion l/8) : 2010 is the last calibrated vrater level available lram the TWDB Llano Uplift GAM" a Since TWDB considers the legal DFC Resolution do€ument5 rather than the Explanatory Report, as the gfficial definition of Dfcs, TWDB does not afficially require {orrections ts the Explanatory Report. However. beciute the Explanatory Repon is often used as i simplmed, mo.e-rea'dable summary of the legal DFC Resolution documents, we recommend correcting the ExplEnatory Report to match the DFC Resolutions tq avoid confusion- Estimated Historical Groundwater Use And 2017 State Water Plan Datasets: Cow Creek Groundwater Conservation District bY Stephen Allen rexaswaternTir*:H:il: Groundwater Technical Assistance Section stephen. allen@twdb.texas. gov (512) 463-7317 August 15, 2019 CROU{IDWATER MAT{AGEME{IIT PLAN DATA: This package of water data reports (paft 1 of a 2-paft package of information) is being provided to groundwater conservation districts to help them meet the requirements for approval of their five- year groundwater management plan. Each report in the package addresses a specific numbered requirement in the Texas Water Development Board's groundwater management plan checklist. The checklist can be viewed and downloaded from this web address: h ttp ://www. twdb. texas. g ou/g rou n dwa ter/docs/GCD/G M PCh eckl ist0 I I 3. pdf The five reports included in this part are: