Substation-Adjacent Datacenter Sites in Washington
At a glance
Parcels sited next to existing transmission substations. Co-location with a substation is the single strongest speed-to-power signal — interconnection distance is measured in feet, not miles.
Top substation-adjacent sites in Washington
| Site | Type | County | Voltage | Capacity | Queue wait | Score |
|---|---|---|---|---|---|---|
| COLUMBIA | Substation-Adjacent | Grant County | 500 kV | 1,000 MW | 3.5 yrs | 69.1 |
| MAPLE VALLEY | Substation-Adjacent | King County | 500 kV | 1,000 MW | 3.5 yrs | 68.4 |
| COVINGTON | Substation-Adjacent | King County | 500 kV | 1,000 MW | 3.5 yrs | 68.2 |
| SNO-KING | Substation-Adjacent | Kitsap County | 500 kV | 1,000 MW | 3.5 yrs | 68.2 |
| TAP200917 | Substation-Adjacent | Snohomish County | 500 kV | 1,000 MW | 3.5 yrs | 68.1 |
| BELL | Substation-Adjacent | Spokane County | 500 kV | 1,000 MW | 3.5 yrs | 68.0 |
| MONROE | Substation-Adjacent | Snohomish County | 500 kV | 1,000 MW | 3.5 yrs | 67.8 |
| UNKNOWN201455 | Substation-Adjacent | Thurston County | 500 kV | 1,000 MW | 3.5 yrs | 67.8 |
| ECHO LAKE | Substation-Adjacent | King County | 500 kV | 1,000 MW | 3.5 yrs | 67.4 |
| SACAJAWEA | Substation-Adjacent | Walla Walla County | 500 kV | 1,000 MW | 3.5 yrs | 67.4 |
| SICKLER | Substation-Adjacent | Chelan County | 500 kV | 1,000 MW | 3.5 yrs | 67.3 |
| CUSTER | Substation-Adjacent | San Juan County | 500 kV | 1,000 MW | 3.5 yrs | 66.9 |
| UNKNOWN206104 | Substation-Adjacent | Grant County | 230 kV | 300 MW | 3.5 yrs | 66.6 |
| RAVER | Substation-Adjacent | King County | 500 kV | 1,000 MW | 3.5 yrs | 66.6 |
| SNOHOMISH | Substation-Adjacent | Snohomish County | 345 kV | 600 MW | 3.5 yrs | 66.5 |
| UNKNOWN209155 | Substation-Adjacent | Grant County | 230 kV | 300 MW | 3.5 yrs | 66.5 |
| TAP206102 | Substation-Adjacent | Grant County | 230 kV | 300 MW | 3.5 yrs | 66.3 |
| TAP206230 | Substation-Adjacent | King County | 500 kV | 1,000 MW | 3.5 yrs | 66.3 |
| LARSON | Substation-Adjacent | Grant County | 230 kV | 300 MW | 3.5 yrs | 66.3 |
| TAP206103 | Substation-Adjacent | Grant County | 230 kV | 300 MW | 3.5 yrs | 66.2 |
| COLUMBIA GENERATING STATION | Substation-Adjacent | Benton County | 500 kV | 1,000 MW | 3.5 yrs | 66.2 |
| TAP203128 | Substation-Adjacent | Walla Walla County | 500 kV | 1,000 MW | 3.5 yrs | 65.9 |
| VANTAGE | Substation-Adjacent | Grant County | 500 kV | 1,000 MW | 3.5 yrs | 65.6 |
| OBRIEN | Substation-Adjacent | King County | 230 kV | 300 MW | 3.5 yrs | 65.2 |
| UNKNOWN206111 | Substation-Adjacent | Grant County | 230 kV | 300 MW | 3.5 yrs | 65.2 |
How does Washington compare with other states for substation-adjacent sites?
With 1,343 sites, Washington ranks 6th of the 52 states that have any substation-adjacent candidate sites. Texas leads with 3,635. Nationally, substation-adjacent sites average 57.4/100 DC Readiness, above the 53.0 average across all site types. Across every site type, Washington averages 51.7, the 42nd-highest of 52 states, and its candidate sites face an average interconnection-queue wait of 3.5 years.
Where are the highest-scoring substation-adjacent sites in Washington?
The top 25 range from 69.1 to 65.2 on the 0–100 DC Readiness Score. They are concentrated in Grant County (8), King County (6), Snohomish County (3) and Walla Walla County (2). By grid region, 25 are in WECC.
County pages: Grant County · King County · Snohomish County · Walla Walla County
What power, fiber and flood exposure do these substation-adjacent sites have?
Of the top 25 substation-adjacent sites in Washington, 25 have a recorded nearest-substation voltage, with a median of 500 kV; for 25 that substation is rated 230 kV or higher. Their counties have a median of 11 fixed fiber broadband providers in FCC data. The median distance to the nearest internet exchange facility is 19 km. The median interconnection-queue wait in their markets is 3.5 years. None of the 5 with a mapped FEMA flood zone sits in a high-risk (A or V) zone.
Frequently asked questions
How many substation-adjacent datacenter sites are in Washington?
GridCensus catalogs 1,343 substation-adjacent datacenter candidate sites in Washington, 3% of the national total for this type (6th of 52 states).
What is a substation-adjacent datacenter site?
Parcels sited next to existing transmission substations. Co-location with a substation is the single strongest speed-to-power signal — interconnection distance is measured in feet, not miles.
What is the best substation-adjacent datacenter site in Washington?
By DC Readiness Score, COLUMBIA in Grant County ranks first at 69.1/100, followed by MAPLE VALLEY in King County at 68.4.
Which Washington counties have the best substation-adjacent sites?
The top 25 substation-adjacent sites in Washington are concentrated in Grant County (8), King County (6), Snohomish County (3) and Walla Walla County (2).
How does Washington score for datacenters overall?
All 6,019 scored sites in Washington average 51.7/100 DC Readiness, the 42nd-highest of 52 states, against a national average of 53.0.
More on substation-adjacent sites and Washington
- All datacenter sites in Washington· 6,019 sites
- Substation-Adjacent datacenter sites nationwide· 38,820 sites
- Federal Excess sites in Washington· 3,676 sites
- Industrial sites in Washington· 538 sites
- Former Mine sites in Washington· 321 sites
- Greenfield sites in Washington· 133 sites
- Brownfield sites in Washington· 8 sites
Substation-Adjacent sites in other states
- Substation-Adjacent sites in Texas· 3,635 sites
- Substation-Adjacent sites in California· 1,573 sites
- Substation-Adjacent sites in Florida· 1,539 sites
- Substation-Adjacent sites in Georgia· 1,530 sites
- Substation-Adjacent sites in Oklahoma· 1,344 sites
- Substation-Adjacent sites in Minnesota· 1,270 sites
- Substation-Adjacent sites in Kentucky· 1,261 sites
- Substation-Adjacent sites in Wisconsin· 1,248 sites
Dataset updated . Screening estimates derived from public data sources.
About this data
Source: GridCensus composite of HIFLD transmission and substation data, EIA, FEMA National Risk Index, FCC broadband data, PeeringDB and ISO interconnection queues, as published November 12, 2026 — GridCensus refreshes it monthly. See the methodology for how records are matched, cleaned and scored.
Cite as: GridCensus, “Substation-Adjacent datacenter sites in Washington”, https://gridcensus.com/site-types/substation/washington (data as of November 12, 2026).
Go deeper than the public screen
Every site and score for Substation-Adjacent sites in Washington is free to browse. Pro adds Watchtower on 25 sites, alerts when new candidate sites, datacenters or interconnection-queue requests appear in your markets, score and capacity history, and CSV export. Enterprise adds team seats, weekly data files for all 147,272 sites, the REST API and an MCP server for AI tools.