WESTSIDE
SubstationWashington · AVISTA CORP
At a glance
WESTSIDE is an electric transmission substation in Washington, on AVISTA CORP's transmission network. It is classified as high-voltage (230 kv) and connects 5 transmission lines. Substation proximity is one of the strongest speed-to-power signals for siting a datacenter — interconnection distance to an energized, high-voltage bus is often the binding constraint on time-to-energization.
Voltage & classification
Ownership
Connected transmission lines
Lines terminating at or passing through this substation, by HIFLD line ID, highest voltage first.
| Line ID | Voltage | Owner | Status | Length |
|---|---|---|---|---|
| #201039 | 230 kV | BONNEVILLE POWER ADMINISTRATION | — | 77.2 mi |
| #201040 | 230 kV | BONNEVILLE POWER ADMINISTRATION | — | 9.6 mi |
| #204067 | 115 kV | AVISTA CORP | — | 4.5 mi |
| #204068 | 115 kV | AVISTA CORP | — | 4.0 mi |
| #204070 | 115 kV | AVISTA CORP | — | 2.0 mi |
Nearby datacenter candidate sites
Scored candidate sites within roughly 25 miles of WESTSIDE, ranked by DC Readiness. Sites this close to an energized substation carry a strong speed-to-power advantage.
| Site | Type | State | County | Voltage | Capacity | Queue wait | Score |
|---|---|---|---|---|---|---|---|
| BELL | Substation-Adjacent | WA | Spokane County | 500 kV | 1,000 MW | 3.5 yrs | 68.0 |
| OZ Spokane | Greenfield | WA | Spokane | — | — | 3.5 yrs | 65.4 |
| UNKNOWN201468 | Substation-Adjacent | WA | Spokane County | 230 kV | 300 MW | 3.5 yrs | 64.7 |
| BEACON | Substation-Adjacent | WA | Spokane County | 230 kV | 300 MW | 3.5 yrs | 63.9 |
| WESTSIDE | Substation-Adjacent | WA | Spokane County | 230 kV | 300 MW | 3.5 yrs | 63.4 |
| Greenfield (BELL - TAFT) | Greenfield | AZ | Spokane County | 500 kV | 1,000 MW | 3.5 yrs | 61.4 |
| TAP205391 | Substation-Adjacent | WA | Spokane County | 138 kV | 100 MW | 3.5 yrs | 60.7 |
| UNKNOWN205382 | Substation-Adjacent | WA | Spokane County | 115 kV | 100 MW | 3.5 yrs | 60.7 |
How does WESTSIDE compare with other substations in Washington?
Washington has 2,106 substation records in HIFLD, of which 785 carry a station name; the rest are unnamed tap points, risers and line ends. 103 named substations in the state are in WESTSIDE's 230–344 kV band (13% of named stations). 34 sit in a higher band. 34 named substations in Washington operate at 345 kV or above. The highest voltage recorded in the state is 500 kV, and the state median is 115 kV.
Who owns the transmission lines at WESTSIDE?
The 5 connected lines listed above are owned by BONNEVILLE POWER ADMINISTRATION, AVISTA CORP. Line voltages range from 115 kV to 230 kV. Their combined recorded length is about 97.2 miles.
How do candidate sites near WESTSIDE score?
The 8 highest-scoring candidate sites within about 25 miles range from 61 to 68 on the 0–100 DC Readiness scale. They fall in Spokane County, Spokane. The Washington average across 6,019 scored sites is 51.7. 1,343 of those Washington sites are classed as substation sites (candidate locations generated at an existing substation).
Frequently asked questions
What voltage is WESTSIDE substation?
WESTSIDE has a maximum voltage of 230 kV and a minimum of 115 kV. That places it in the 230–344 kV band. The median named US substation in this dataset is 115 kV, so WESTSIDE is above the national midpoint.
How many transmission lines connect to WESTSIDE substation?
5 transmission lines terminate at or pass through WESTSIDE in the HIFLD line data. The connected lines listed here run at 230 kV, 115 kV. Together the listed lines cover about 97.2 miles.
Who owns WESTSIDE substation?
HIFLD does not publish substation owners directly. Most of the transmission lines that end at WESTSIDE belong to AVISTA CORP, and others to BONNEVILLE POWER ADMINISTRATION. GridCensus derives this from the line data, so confirm ownership with the utility for anything contractual.
Where is WESTSIDE substation located?
WESTSIDE is in Washington at 47.7280, -117.5041. The datacenter candidate sites closest to it are in Spokane County, Spokane.
Are there datacenter candidate sites near WESTSIDE substation?
GridCensus lists at least 8 scored candidate sites within roughly 25 miles of WESTSIDE. The highest-scoring is BELL at 68/100. Across Washington, the average DC Readiness score is 51.7.
Other 230 kV substations in Washington
- MIDWAY· 16 lines
- WHITE RIVER· 16 lines
- SHELTON· 15 lines
- TALBOT HILL· 15 lines
- BEACON· 14 lines
- LONGVIEW1· 14 lines
- OBRIEN· 14 lines
- BOTHELL· 13 lines
- All named substations in Washington· 785 stations
- Datacenter candidate sites in Washington· 6,019 sites
- Brownfield and retired plant sites in Washington
- Substations by state
About this data
Source: HIFLD Electric Substations and Transmission Lines (U.S. Department of Homeland Security), as published June 29, 2026. See the methodology for how records are matched, cleaned and scored.
Cite as: GridCensus, “WESTSIDE substation, Washington”, https://gridcensus.com/substations/washington/westside-8bc89d7d (data as of June 29, 2026).
Dataset updated . Screening estimates derived from public data sources.
Substation attributes are derived from public HIFLD / EIA infrastructure data and may lag real-world upgrades or retirements. Voltage and connected-line counts are screening figures — confirm available capacity and interconnection terms directly with the operating utility and ISO.
Go deeper than the public screen
Every site and score for WESTSIDE substation, 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.