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Data Center Water Impact Assessment Tool

WaterMark / Jurisdictions / Santa Clara County, CA (Silicon Valley)

Santa Clara County, CA (Silicon Valley): Data Center Water Impact

Reference data for evaluating a data center proposal in Santa Clara County, CA (Silicon Valley). 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 utilityValley Water (SCVWD) / San Jose Water CompanyUtility of record
Supply sourceGuadalupe / Coyote watersheds + imported State Water Project & groundwaterUtility of record
Treatment capacity380 MGDWater stress: WRI Aqueduct 4.0 (Kuzma et al. 2023), Guadalupe basin HUC-8 18050003, High category. Utility supply: Valley Water (Santa Clara Valley Water District) is the county wholesale supplier; San Jose Water serves the retail core.
Water rate$8.37 / 1,000 galValley Water (SCVWD) / San Jose Water Company published rate schedule
Watershed stressHigh (3.6 / 5)Water stress: WRI Aqueduct 4.0 (Kuzma et al. 2023), Guadalupe basin HUC-8 18050003, High category. Utility supply: Valley Water (Santa Clara Valley Water District) is the county wholesale supplier; San Jose Water serves the retail core.

Watershed consumptive use

Basin: Guadalupe (HUC-8 18050003). Figures are consumptive use, not withdrawal, because evaporative data center loss is consumptive. USGS data year 2015.

CategoryConsumptive use (MGD)Share of basin
Residential 197.3 90.5%
Thermoelectric power 0.25 0.1%
Industrial 12.48 5.7%
Irrigation 8.1 3.7%
Mining 0 0.0%
Existing data centers 0 0.0%
Total218.1100.0%

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), Santa Clara County, CA. Values are 2015 freshwater withdrawals (Mgal/d): PS 194.59 + DO 2.70 = residential 197.3; IN 12.48; IR 8.10; MI 0.00; PT 0.25.

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 / CAISO (CA)CAISO
Electric utilitySilicon Valley Power (Santa Clara) / PG&EUtility of record
Grid water intensity0.18 gal / kWhMacknick et al. 2012 recirculating-cooling consumption factors, weighted by the CAISO/California generation + import mix (gas ~37%, solar ~32%, hydro ~11%, nuclear ~9%, wind ~8%) per EIA California state profile 2024. Derived ~0.18 gal/kWh (thermal share dominates a low-water grid).
Local peak demand410 MWCAISO
Modeled rate impact8% to 18%See methodology

Where this water is consumed: CAISO generation serving Silicon Valley draws on gas/solar/imports largely outside the Guadalupe HUC; thermoelectric withdrawal within the county is negligible (0.25 Mgal/d, 2015). Scope 2 water is consumed at generation sites elsewhere in WECC.

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 Santa Clara County, CA (Silicon Valley) 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.

Regulatory and siting status

Silicon Valley. Dense legacy DC cluster on Silicon Valley Power (~55% of the municipal utility load). High water stress and State Water Project import dependence. California regulatory friction (CEQA, local) is the highest in the set; weak DC tax incentives. Low-water CAISO grid is the offsetting strength.

Sources: Water: Valley Water / San Jose Water. Grid: CAISO (Silicon Valley Power / PG&E).

Comparative siting scores for this county, alongside every other county tracked, are on the US Siting Matrix.

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.