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Data Center Water Impact Assessment Tool

WaterMark / Jurisdictions / Pinal County, AZ (Casa Grande / Eloy)

Pinal County, AZ (Casa Grande / Eloy): Data Center Water Impact

Reference data for evaluating a data center proposal in Pinal County, AZ (Casa Grande / Eloy). Every figure below is a stored value with its primary source attached. Facility-scale results are produced by the assessment tool.

Water supply

MetricValueSource / basis
Water utilityArizona Water Company (Pinal Valley) / CAP + groundwaterUtility of record
Supply sourceGroundwater + Central Arizona Project (Colorado River) — Pinal AMAUtility of record
Treatment capacity60 MGDWater stress: WRI Aqueduct 4.0 (Kuzma et al. 2023), Middle Gila basin HUC-8 15050100, Extremely High category (Lower Gila/Pinal AMA, severe groundwater overdraft). Utility: Arizona Water Company, Casa Grande / Pinal Valley.
Water rate$3.39 / 1,000 galArizona Water Company (Pinal Valley) / CAP + groundwater published rate schedule
Watershed stressExtremely High (4.6 / 5)Water stress: WRI Aqueduct 4.0 (Kuzma et al. 2023), Middle Gila basin HUC-8 15050100, Extremely High category (Lower Gila/Pinal AMA, severe groundwater overdraft). Utility: Arizona Water Company, Casa Grande / Pinal Valley.

Watershed consumptive use

Basin: Middle Gila (HUC-8 15050100). Figures are consumptive use, not withdrawal, because evaporative data center loss is consumptive. USGS data year 2015.

CategoryConsumptive use (MGD)Share of basin
Residential 65 6.5%
Thermoelectric power 1.45 0.1%
Industrial 0.23 0.0%
Irrigation 935.11 93.2%
Mining 2.08 0.2%
Existing data centers 0 0.0%
Total1003.9100.0%

Total is the sum of the categories listed above. Shares are each category divided by that total. Source: USGS Estimated Use of Water 2015, county-level data release (Dieter et al. 2018), Pinal County, AZ. Values are 2015 freshwater withdrawals (Mgal/d): PS 63.24 + DO 1.76 = residential 65.0; IN 0.23; IR 935.11; MI 2.08; PT 1.45.

Grid generation water (Scope 2)

Generating the electricity a data center consumes evaporates water at the power plant. That volume is real, it is attributable, and it is excluded from most corporate "water positive" accounting. On a thermal grid it is frequently comparable to the facility's own cooling water.

MetricValueSource / basis
Grid regionWECC (Southwest)Electrical District No. 3 (ED3)
Electric utilityElectrical District No. 3 (ED3)Utility of record
Grid water intensity0.33 gal / kWhMacknick et al. 2012 recirculating-cooling consumption factors, weighted by the WECC-Southwest (AZ) gas + coal + solar mix per EIA Arizona. Same 0.33 gal/kWh basis as the existing chandler-az / mesa-az APS-SRP entries.
Local peak demand480 MWElectrical District No. 3 (ED3)
Modeled rate impact12% to 28%See methodology

Where this water is consumed: WECC-SW thermal generation (gas, retiring coal) serving Pinal sits partly within the Gila system; with Project Bella (480 MW gas + 440 MW battery) sited locally to power the Casa Grande DC corridor, a growing share of Scope 2 water lands in-basin. Irrigation (935 Mgal/d) dominates withdrawals, so the basin is already in severe overdraft.

Run this county at your facility size. The assessment tool computes direct (Scope 1) and indirect (Scope 2) water for a specific load, cooling system, and mitigation stack, with the same citations attached.

Open Pinal County, AZ (Casa Grande / Eloy) in the assessment tool

Reducing the footprint here

A high stress reading is a design constraint, not a verdict. Closed-loop and dry or hybrid cooling, adiabatic assist, immersion, and reclaimed or non-potable sourcing each move the direct number, and siting against a cleaner grid mix moves the indirect number. The solutions catalog lists each option with its water reduction, its energy and cost tradeoff, and its source.

CountyWater sourceWatershed stress
Pima County, AZ (Tucson) Colorado River / Central AZ Project + Aquifer Extremely High (4.2/5)
Chandler, AZ Salt River Project / CAP / Reclaimed High (3.9/5)
Mesa, AZ (Maricopa County) Salt River Project / CAP (Colorado River) + groundwater High (3.8/5)

How these numbers are derived

Assumptions, formulas, and the full source list are in the methodology. WaterMark is published by Standard Water Corp and is not affiliated with any data center developer, utility, or government agency.