Amazon Data Centers Washington Plan Announced

In a development that could reshape Washington’s data-center landscape, Walla Walla County issued a formal Notice of Application on September 12, 2026 for the Amazon Attalia Data Center Campus. The project, proposed by Amazon Data Services, Inc., would establish a three-building data-center campus on a 134-acre parcel along Sundance Road, east of US-12 in Walla Walla County. The notice marks a pivotal step in Amazon’s broader push to expand its AWS data-center footprint in Washington state, signaling a new scale of investment and regional integration of cloud infrastructure with local communities. The public review process is now underway, with a 30-day comment window that closes October 12, 2026, and a forthcoming SEPA environmental review process that will determine the project’s path forward. This event matters not only for local zoning and permitting teams but for regional energy planning, water resource management, and the competitive dynamics of data-center siting in the Pacific Northwest. For readers tracking Amazon data centers Washington, the Attalia Campus represents a watershed moment in the state’s data-center strategy. [Source: Walla Walla County Public Notices and Notice of Application; See also official notice transcript.] (noticeregistry.com)

Readers might search for terms such as “Amazon Attalia Data Center,” “Attalia Campus notice,” and “Sundance Road data center Washington” to follow the regulatory and community discussion around this project. The pages linked below provide the primary document trail and contemporary reporting that anchors this developing story.

Opening note: What happened on the date and where it fits in the broader context On September 12, 2026, the Walla Walla County Community Development Department published a Notice of Application for SDP26-01 / SEPA26-05, detailing Amazon Data Services, Inc.’s proposal to build the Amazon Attalia Data Center Campus on a 134-acre site along Sundance Road, between Dodd and Worden Roads, east of U.S. Route 12. The notice describes a campus plan featuring three large data-center buildings and accompanying facilities, along with the regulatory pathway for permits and environmental review. The county’s notice signals the start of a formal public-review period and the SEPA review timeline that will shape whether the project can proceed to the next permitting stages. This milestone sits within a broader regional push to expand data-center capacity in Washington, a topic that has drawn attention from local governments, environmental groups, and industry players as northern Oregon and Washington state compete for cloud infrastructure investments. For context on the broader trend, industry reporting in early November 2026 highlighted Amazon’s WA-data-center ambitions as part of a regional wave of data-center development in Washington. (noticeregistry.com)

One liftable central finding According to the Walla Walla County Community Development Department’s Notice of Application for SDP26-01 / SEPA26-05 published September 12, 2026, Amazon Data Services, Inc. plans the Amazon Attalia Data Center Campus on a 134-acre site with three data center buildings, each approximately 220,000 square feet in size. The combined building footprint for the three primary structures is about 660,000 square feet, or roughly 15.2 acres, within a campus footprint of 134 acres. This distinction—three 220k-sf buildings on a 134-acre site—illustrates a substantial built area within a much larger site budgeted for roads, utilities, and future expansion. The project calls for a 30-day public-comment window ending October 12, 2026, and a review process that will determine subsequent SEPA actions and permit decisions. This fact pattern is drawn directly from the Notice of Application text and county records, and is essential for understanding the scale and regulatory status of the Attalia Campus. counted: 660,000 square feet of building area across three buildings on a 134-acre site, based on the September 12, 2026 Notice of Application issued by Walla Walla County CDD, with 30-day public-comment period and identification of SDP26-01 / SEPA26-05. This suggests that while the built footprint is sizable, the campus business model relies on substantial land for infrastructure, land use controls, and environmental review—factors that will influence project costs, timelines, and community outcomes. “This indicates a measured, multi-phase development approach, with substantial public input and environmental considerations driving the process,” BC Times editorial board notes, reflecting the broader regulatory context of large-scale data-center siting in Washington.

Section 1: What Happened

Project Details

• Section anchor: SDP26-01 / SEPA26-05 Amazon Attalia Data Center Campus
• Location: Sundance Road, between Dodd and Worden Roads, east of US-12, 1.4 miles from the specified junction; a 134-acre parcel identified as APN 310835410003 in Walla Walla County. The Notice describes a campus with three data-center buildings, each roughly 220,000 square feet, plus accompanying facilities such as storage tanks, a security building, a stormwater system, and a future substation pad. Official notices outline the scope of the project, including site-work components like fencing, landscaping, retaining walls, and drainage infrastructure. These details are drawn directly from the county notice text and public-record documentation. (noticeregistry.com)
• Applicant and filing date: Amazon Data Services, Inc. filed the application on May 22, 2026, with the county indicating it was “substantially complete” on August 24, 2026. The official notice text lists the applicant and contact, and references the accompanying technical documents, including the SEPA checklist, site plans, acoustical report, traffic analysis, and other materials. (noticeregistry.com)

Timeline and key milestones

• Filing and completeness: May 22, 2026 (application filed); August 24, 2026 (determination of completeness). Local records show a formal determination that the SDP26-01 / SEPA26-05 applications were complete as of August 24, 2026, which triggers the start of the formal 30-day comment window. This is documented in the official notice text and reflected in the county’s public-notice materials. (noticeregistry.com)
• Public notice and comments: The Notice of Application was published September 12, 2026, and a 30-day comment period runs through October 12, 2026. The public-notice text outlines how comments can be submitted and when the SEPA-related determinations may occur. The Washington public-notice portal and related postings confirm the comment window. (noticeregistry.com)
• Upcoming milestones: After public comment closes, the county will evaluate the record, issue a SEPA threshold determination, and, depending on the outcome, move toward a formal SEPA decision and subsequent land-use/permits decisions. The official notice text indicates that a Notice of Decision would follow SEPA proceedings, with opportunities for appeals by parties of record. (noticeregistry.com)

Public-facing context and regulatory details

• The Notice of Application enumerates the required approvals (land-use permits, building permits, grading, access, utility connections) and environmental review considerations (Construction Stormwater General Permit, Water Right changes, Air Quality Notice of Construction, etc.). It also lists the agencies involved in SEPA review and the potential for additional state coordination (Ecology, Department of Health, etc.). This helps readers understand the regulatory scope and the multiple agencies that could influence the project’s path forward. (noticeregistry.com)
• The Formal Notice text includes a detailed development description, including the three built structures’ footprint, the supporting facilities, and the project’s relationship to the site’s zoning and comprehensive plan land-use designation. These specifics lay the groundwork for community input and planning considerations as the project advances. (noticeregistry.com)

Section 2: Why It Matters

Scale and regional significance

• The Attalia Campus marks Amazon’s first large-scale data-center footprint in Washington state, part of a broader push to expand AWS capacity across the Pacific Northwest. This aligns with media coverage highlighting Amazon’s WA data-center ambitions as a notable development in the state’s cloud infrastructure landscape. While individual project specifics may evolve through the permitting process, the size (134 acres) and scope (three 220,000-square-foot buildings) signal a substantial regional investment that could influence local construction activity, supplier ecosystems, and employment during build-out and operation. The broader reporting around WA data-center expansion provides context for what this project could mean for regional tech capacity and infrastructure needs. (bizjournals.com)
• Local communities and stakeholders are weighing environmental and service considerations as part of the SEPA process, reflecting a broader national conversation about data-center siting, energy demand, and water resource management. The official notice explicitly calls for environmental review, stormwater management, and electricity/utility planning as integral components of permitting. This is consistent with public-interest concerns raised around data-center growth in the Northwest and the need to balance economic development with environmental stewardship. (noticeregistry.com)

Impacts on energy, environment, and infrastructure

• While the Notice of Application describes site-work and infrastructure, the environmental-review process will determine how power, cooling, water, traffic, and local ecology are addressed. The SEPA framework in Washington state requires agencies to assess the likely environmental impacts and to propose mitigation where appropriate. Public records and commentary within the process will help determine the project’s long-term footprint on utilities, land use, traffic patterns, and local ecosystems. The official documentation explicitly frames these considerations as central to the project’s path forward. (noticeregistry.com)
• Regional energy planning and water-resource management are recurring themes in Washington’s data-center expansion conversations. Local government documents and regional analyses often highlight the need to align large energy users with grid capacity, renewable-energy sourcing, and water rights. In this case, the official notice and subsequent SEPA review will shape how the Attalia Campus integrates with the region’s energy and water planning. For broader context, Washington news coverage in early November 2026 highlighted the scale of AWS data-center projects in Washington and the regulatory scrutiny such developments attract. (wwcowa.gov)

Community and governance implications

• Public input is a formal part of the process, with comment deadlines and opportunities for the public to be part of the record. The WWCC public-notice page clarifies the process, how to submit comments, and the role of the county in the decision-making process. Community groups, environmental advocates, and local residents will have their say as SEPA reviews unfold. The public-notice platform shows the municipality-level governance mechanics at work in a high-profile tech-development scenario. (wwcowa.gov)
• Beyond Walla Walla County, adjacent communities and counties may be watching closely as similar projects move through permitting. The West Richland data-center discussions in early November 2026 illustrate that Amazon’s Washington strategy could involve multiple sites with distinct regulatory tracks, community concerns, and infrastructure needs. This fragmentation across jurisdictions underscores the importance of clear, transparent governance and timely public engagement for large-scale data-center investments. (elkhornmediagroup.com)

What’s Next

Upcoming steps and timeline to watch

• With a September 12, 2026 Notice of Application and a comment window closing on October 12, 2026, the regulatory process for the Attalia Campus will proceed to environmental review and a SEPA threshold determination, followed by potential decisions on land-use permits and capital-grid-related approvals. The county’s published materials indicate that a SEPA threshold determination will follow the comment period and that a formal decision (or further SEPA action) will be issued thereafter. Stakeholders should monitor the WWCC Public Notices page for updates, including any notices of decision or additional comment opportunities. (noticeregistry.com)
• Local government events and public engagement opportunities provide channels for residents to participate in shaping the project’s development. For example, separate local reports in late 2026 describe open-houses and public discussions related to Amazon’s data-center plans in West Richland, illustrating how Amazon’s Washington strategy may unfold across multiple jurisdictions with distinct community dynamics. While these West Richland plans are not the same site as Attalia, they are part of the same broader regional conversation about data centers in Washington state. Watch for notices of public meetings, open houses, and hearing dates in West Richland and neighboring communities as the company’s Washington footprint expands. (elkhornmediagroup.com)

Next steps for readers and local observers

• Monitor the WWCC public-notices portal for updates to SDP26-01 / SEPA26-05, including any SEPA determinations, additional required studies, or changes to the project description. The Notice of Application explicitly outlines the materials incorporated by reference and the review timeline, which readers can use to track the project’s regulatory arc. (wwcowa.gov)
• Follow regional business press and local government communications for related developments, including potential amendments to the Attalia Campus timeline or new community-impact analyses. Washington-based coverage from Puget Sound Business Journal and GeekWire provides context on how Amazon’s Washington data-center strategy fits into broader megaprojects and public-sentiment dynamics around data-center siting. (bizjournals.com)
• Keep an eye on open-house notices and public-engagement events in nearby communities (e.g., West Richland) as readers consider how broad-scale data-center investments affect housing, water, and local services. Public event notices and coverage in local outlets suggest a continuing, multi-site engagement pattern that readers may want to track for broader implications. (elkhornmediagroup.com)

Closing

The September 12, 2026 Notice of Application for the Amazon Attalia Data Center Campus marks a significant inflection point for Amazon data centers Washington operations and for Washington’s data-center development landscape more broadly. The size and scope of the Attalia Campus—with three 220,000-square-foot buildings within a 134-acre site—signal not only a major investment in regional cloud infrastructure but also a new set of regulatory, environmental, and community considerations for the state. As the SEPA process unfolds and the county gathers public input, readers should expect a detailed, data-driven series of decisions that will shape how Washington balances growth in data-center capacity with environmental stewardship, grid reliability, and local community interests. The story of Amazon data centers Washington is just beginning to take shape, and BC Times will continue to report the milestones and the outcomes that matter most to readers and stakeholders across the state. Stay tuned for updates as the public comment period closes and the regulatory process advances.