Data Center Site Selection in Washington State

Most of Washington’s large data center capacity is east of the Cascades, in three counties along the Columbia River. Grant County, with Quincy at its center, is the largest cluster: Grant PUD serves eight data center operators, which accounted for about 280 average megawatts of load in 2025.¹ Across the river, Douglas County hosts campuses in East Wenatchee, including Sabey’s, and a Microsoft load of 180 MW served under a 2023 agreement with Douglas County PUD.¹⁰³ In Chelan County, home to Wenatchee, the PUD reported in 2024 that a Microsoft data center was under construction in the Malaga area.²

The common thread is the serving utility. All three counties are served by public utility districts that own large hydroelectric projects on the Columbia, rather than by an investor-owned utility. Each PUD is governed by an elected commission, sets its own rates and decides for itself how to treat large new loads. That makes a central Washington site screen a utility-by-utility exercise. Our Pacific Northwest guide covers the regional system, and the hydropower guide explains what dam-backed supply can and cannot offer a new campus.

West of the Cascades, the Seattle area has enterprise and colocation capacity close to fiber and customers, but land costs are higher and the sales tax exemption is limited to rural counties, which leaves out the most populous metro areas.⁴ Large campuses therefore cluster where both the exemption and PUD power are available. For a comparison with the Columbia River sites on the other side of the state line, see our Oregon guide.

Central Washington’s low-cost reputation comes from PUD-owned dams, but the PUDs have spent more than a decade separating new large loads from that legacy supply. In 2015, Chelan PUD modified a pause on new large loads so that it applied only to customers using 250 kWh per square foot or more per year, rather than to every applicant for 1 MW or more, and proposed a separate high-density load rate for server farms.¹¹ Douglas County PUD’s 180 MW Microsoft agreement runs from January 2023 to December 31, 2029, timed to finish before Washington’s 2030 clean energy requirements take hold.³

Chelan PUD’s 2024 framework is the clearest statement of how a PUD now thinks about data centers. Its guiding principles are a neutral-to-positive impact on other customers, reliability, stable and predictable rates, local control, and protection of the PUD’s existing hydropower marketing strategy. It offers three paths: short-term market supply, power the customer procures itself, or a negotiated contract that may include PUD generation, and each arrangement goes to the board for approval.² Staff also noted that a typical large data center could more than double the existing load in Chelan PUD’s territory.²

The logic is the same across the three PUDs. Hydro output already serves existing customers and supports wholesale sales that help hold down local rates, and Chelan PUD lists protecting that marketing strategy as a guiding principle.² A new campus is therefore priced at what new or market supply costs, not at the cost of the dam.

Grant PUD is the utility most site seekers call first, and its queue shows why central Washington is now a constrained market. As of August 2024, the PUD had 75 applications for new and expanding power service, and the Quincy area alone accounted for 1,578 MW of requested load.⁵ Compare that with the roughly 280 average megawatts its eight data center operators used in 2025.¹

The rate structure separates existing industrial customers from new large loads. Grant PUD’s Rate Schedule 15, Large Industrial, applies to industrial customers with billing demand of 10 MW or more and took effect for meter readings after April 1, 2025, with a demand charge of $6.03 per kW of billing demand. But any load that is or becomes a New Large Load under the PUD’s customer service policies is served under Rate Schedule 94 instead.⁶ Read the definition of a New Large Load closely: an expansion of an existing account can trigger it.

Rates are still moving. At a September 15, 2026 workshop, staff proposed new rate classes for 2027: a Tier 2 group including Rate 20, High Density Compute, and Rate 21, Large High-Density Compute, would see an average increase of 12.5%, against 9.5% for the Tier 1 industrial classes.⁷ As of October 2026 these were proposals, not adopted rates. Our guide to large-load tariffs and electric service agreements covers the contract terms to expect.

Three forces make new power scarce in central Washington. First, the hydro is spoken for: PUD output already serves existing customers and wholesale sales, so new load means buying or building new supply.² Second, regional demand is rising fast. The Northwest Power and Conservation Council’s 2025 forecast found that electricity demand in the Northwest could double over the next 20 years, with data centers a main driver of near-term growth.¹²

Third, state law limits what that new supply can be. The Clean Energy Transformation Act required utilities to stop serving Washington customers with coal-fired power by the end of 2025, requires carbon-neutral electricity by 2030, and requires all retail electricity to come from renewable or non-carbon sources by 2045.⁹ For a data center, that means new gas generation is a harder fit than in states such as Louisiana or Texas, and contracts for new clean resources carry the cost of new projects. Douglas County PUD timed its Microsoft agreement to end before the 2030 requirements take effect.³

Transmission adds a fourth limit. A parcel near a dam does not automatically have access to its output, and new substation and line work can set the energization date. Ask the PUD what upgrades your load would trigger and whether it would be served from an existing substation. Douglas County PUD, for example, added 18 MW of reserve power for Sabey’s East Wenatchee campus through its Pangborn Substation under an interconnection and service agreement.¹⁰

Washington’s data center sales tax exemption, in RCW 82.08.986 and 82.12.986, is the main state incentive, and it is limited by geography. According to the Department of Revenue, a computer data center qualifies if it is in a rural county as defined in RCW 82.14.370, has at least 20,000 square feet dedicated to housing working servers, and begins construction after March 31, 2010 and before July 1, 2035 (excluding July 1, 2011 through March 31, 2012).⁴ The exemption covers eligible server equipment and the labor to install it, plus eligible power infrastructure.⁴

The exemption has been reviewed before. JLARC’s 2016 review recommended continuing it, finding that the goals of higher rural property values and property taxes from data center investment were being met, while urging the Legislature to check periodically whether the benefits exceed the long-term cost.¹³ In 2025, Gov. Bob Ferguson’s data center work group debated a draft recommendation that would have tied the tax break to clean power sourcing while extending it to data centers statewide; it was the one draft recommendation of nine expected to be left out of the final report.¹⁴

In 2026, the Legislature narrowed the incentive instead. SB 6231 removes the exemption for replacing server equipment at existing data centers starting July 1, 2026, while preserving it for new facilities; the Department of Revenue estimated $63.1 million in added revenue in the current biennium and $143.9 million in 2027–29.⁸ A broader bill, HB 2515, which would have regulated data center electricity rates and environmental impacts, did not pass after Microsoft came out against it.¹⁵ Expect the debate to return, and confirm eligibility with a Washington tax advisor. Our sales tax exemptions by state guide compares Washington with other states.

Quincy shows both the water problem and one answer to it. The city gets about 7.8 inches of rain a year, and five groundwater wells supply all of its residential, commercial and industrial water.¹⁶ The local groundwater is high in total dissolved solids, which causes problems in data center cooling equipment.¹⁶

The city’s Water Reuse Utility, built with Microsoft at a cost of about $31 million, treats cooling water from Microsoft’s data center and returns it for reuse. It includes 10 treatment systems linked by more than 30 miles of pipe across Quincy’s industrial area, concentrates salts in lined brine ponds and does not discharge to the environment or the city’s wastewater plant. EPA’s case study reports a demand offset of 138 million gallons per year.¹⁶

For a new site, the lesson is that water in central Washington is an infrastructure question as much as a supply question. Ask the city or water district whether a reuse or industrial water system can serve the parcel, what the discharge path is for cooling blowdown, and whether a closed-loop design would avoid the issue. Water rights in Washington follow prior appropriation; our guides to water rights and groundwater and reclaimed water for cooling go further.

1. 01Confirm the serving PUD and whether the parcel is in a rural county that qualifies for the exemption.⁴
2. 02Ask the PUD which large-load schedule or framework applies, and whether your ramp would make the account a new large load.⁶²
3. 03Ask where the request would sit in the queue and which substation and transmission upgrades it would need.⁵
4. 04Plan for supply that meets state clean energy rules after 2030, and price it as new supply, not legacy hydro.⁹
5. 05Map the water source and discharge path, and check whether a reuse system is available.¹⁶
6. 06Confirm tax eligibility for the actual owner and equipment, including the 2026 change for server replacement.⁸

Central Washington still has what made it attractive: PUD-owned hydro, a dry climate and an established workforce around existing campuses. What has changed is that power is allocated deal by deal. Our methodology explains how we weigh utility, water and incentive questions together, and you can get a site reviewed to test a specific parcel.