Seattle pauses large data centers as utility-cost fight begins

Seattle has put a one-year emergency pause on new or expanded large data centers, moving a fast-growing AI infrastructure fight from abstract technology policy into city zoning, water demand and electric bills.

The City Council passed CB 121214 on June 9, 2026, and Mayor Katie Wilson signed it as Ordinance 127447 on June 11. City records list the ordinance as passed and signed, with an immediate effective date because it was adopted as an emergency measure.

For residents and small businesses, the central issue is not only whether Seattle should host more data-center infrastructure. It is also whether the upgrades needed to serve high-demand projects would affect electric rates, water systems, land use and neighborhoods near industrial sites.

What the moratorium does

The ordinance applies citywide, in all zones, to covered data centers. During the moratorium, Seattle may not file, accept, process or approve applications to establish or expand a covered data center, or to change another use into a covered data center, whether the data center would be the main use or an accessory use.

The pause is not a permanent ban. The ordinance runs for 365 days from its effective date unless the City Council ends it sooner or extends it under state law. The council also must hold a public hearing within 60 days of adoption.

The new city code definition covers facilities used primarily for housing, operating or co-locating computer and networking equipment and handling digital data, with capacity above 20 Megavolt-Amperes. The definition also points to infrastructure commonly associated with those facilities, including cooling systems, backup power systems, battery storage and uninterruptible power supplies.

The ordinance does not shut down existing facilities. It also includes a limited exemption for an operating facility that expands capacity by no more than an additional 20 MVA, if it was operating on the ordinance’s effective date and meets the conditions in the ordinance.

Why utility bills are part of the zoning debate

Seattle City Light has separately described a proposed large-load rate policy as a way to prevent costs from new high-demand customers from shifting to existing customers. In a June 12 Powerlines update, the utility said serving large new loads can require wholesale power purchases and major infrastructure investments, and that existing residents and local businesses should not have to absorb costs tied to new large business customers.

That makes the rate discussion a pocketbook issue for renters, homeowners, employers and storefronts that already pay into the electric system. The data-center moratorium controls land-use permitting inside city limits. Seattle City Light’s rate-policy work is a related but separate question about how large new electrical loads would be priced and connected.

The ordinance’s findings list concerns that include electric and water infrastructure, utility affordability and reliability, jobs, economic development, public health, environmental impacts, noise, heat and emissions. It also says the city recognizes that data centers can support business, government, health care, education and public-safety uses, which is why the current action is framed as a pause for study rather than a rejection of the technology sector.

What city departments must study next

The work plan attached to the ordinance directs the Office of Sustainability and Environment, Seattle City Light, Seattle Public Utilities, the Seattle Department of Construction and Inspections and other relevant departments to analyze data-center impacts and send reports or legislation to the council.

The first deadline is close: Seattle City Light’s analysis and proposal on electricity is due July 1, 2026. Seattle Public Utilities’ water analysis and proposal is due October 30, 2026. SDCI is directed to study zoning and development standards, with proposed legislation expected by January 2027 for anticipated council action by March 2027. The Office of Sustainability and Environment is assigned to lead work on a community-benefits framework by February 1, 2027.

Local reporting has already pointed to SODO as one focal point. KUOW reported on a proposed nine-story data center south of the Spokane Street Viaduct, while KIRO 7 reported that residents testified in support of the one-year pause before the council vote.

For Seattle readers, the next year will determine more than whether a particular data-center project can move forward. Watch for utility-rate decisions, public hearings, department reports, any exemption requests, and permanent zoning or fee proposals that could decide where large data centers may be allowed and who pays for the power and water infrastructure they require.

Sources

• Seattle City Council legislative record for CB 121214
• Seattle City Light Powerlines update on data center power demand
• KUOW report on Seattle AI data center moratorium bill