PIONEER
SubstationCalifornia · MERCED IRRIGATION DISTRICT
At a glance
PIONEER is an electric transmission substation in California, on MERCED IRRIGATION DISTRICT's transmission network. It is classified as distribution (69–115 kv) and connects 2 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 |
|---|---|---|---|---|
| #303167 | 115 kV | MERCED IRRIGATION DISTRICT | IN SERVICE | 16.4 mi |
| #307059 | 115 kV | MERCED IRRIGATION DISTRICT | IN SERVICE | 12.0 mi |
Nearby datacenter candidate sites
Scored candidate sites within roughly 25 miles of PIONEER, 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 |
|---|---|---|---|---|---|---|---|
| PRESCOTT | Substation-Adjacent | CA | Stanislaus County | 230 kV | 300 MW | 7.6 yrs | 57.1 |
| ROSEMORE B | Substation-Adjacent | CA | Stanislaus County | 230 kV | 300 MW | 7.6 yrs | 57.0 |
| LOS BANOS | Substation-Adjacent | CA | Merced County | 500 kV | 1,000 MW | 7.6 yrs | 56.5 |
| PARKER | Substation-Adjacent | CA | Stanislaus County | 230 kV | 300 MW | 7.6 yrs | 56.1 |
| Turlock Irrigation District Fuel Cell | Brownfield | CA | Stanislaus County | 66 kV | 1 MW | 7.6 yrs | 55.9 |
| WALNUT | Substation-Adjacent | CA | Stanislaus County | 230 kV | 300 MW | 7.6 yrs | 55.5 |
| OZ Stanislaus | Greenfield | CA | Stanislaus | — | — | 7.6 yrs | 55.4 |
| COTTLE | Substation-Adjacent | CA | Stanislaus County | 230 kV | 300 MW | 7.6 yrs | 55.4 |
How does PIONEER compare with other substations in California?
California has 4,260 substation records in HIFLD, of which 3,003 carry a station name; the rest are unnamed tap points, risers and line ends. 379 named substations in the state are in PIONEER's 69–114 kV band (13% of named stations). 1,125 sit in a higher band. 44 named substations in California operate at 345 kV or above. The highest voltage recorded in the state is 500 kV, and the state median is 69 kV.
Who owns the transmission lines at PIONEER?
The 2 connected lines listed above are owned by MERCED IRRIGATION DISTRICT. Line voltages range from 115 kV to 115 kV. Their combined recorded length is about 28.4 miles.
How do candidate sites near PIONEER score?
The 8 highest-scoring candidate sites within about 25 miles range from 55 to 57 on the 0–100 DC Readiness scale. They fall in Stanislaus County, Merced County, Stanislaus. The California average across 8,490 scored sites is 45.4. 1,573 of those California sites are classed as substation sites (candidate locations generated at an existing substation).
Frequently asked questions
What voltage is PIONEER substation?
PIONEER has a maximum voltage of 69 kV and a minimum of 115 kV. That places it in the 69–114 kV band. The median named US substation in this dataset is 115 kV, so PIONEER is below the national midpoint.
How many transmission lines connect to PIONEER substation?
2 transmission lines terminate at or pass through PIONEER in the HIFLD line data. The connected lines listed here run at 115 kV. Together the listed lines cover about 28.4 miles.
Who owns PIONEER substation?
HIFLD does not publish substation owners directly. Most of the transmission lines that end at PIONEER belong to MERCED IRRIGATION DISTRICT. GridCensus derives this from the line data, so confirm ownership with the utility for anything contractual.
Where is PIONEER substation located?
PIONEER is in California at 37.3974, -120.7270. The datacenter candidate sites closest to it are in Stanislaus County, Merced County, Stanislaus.
Are there datacenter candidate sites near PIONEER substation?
GridCensus lists at least 8 scored candidate sites within roughly 25 miles of PIONEER. The highest-scoring is PRESCOTT at 57/100. Across California, the average DC Readiness score is 45.4.
Other 69 kV substations in California
- SMARTSVILLE· 8 lines
- EL CAJON· 6 lines
- RIVERSIDE· 6 lines
- ROSE CANYON· 6 lines
- BERNARDO· 5 lines
- DEL MAR· 5 lines
- BORDER· 4 lines
- CENTERVILLE· 4 lines
- All named substations in California· 3,003 stations
- Datacenter candidate sites in California· 8,490 sites
- Brownfield and retired plant sites in California
- 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, “PIONEER substation, California”, https://gridcensus.com/substations/california/pioneer-6d0cfd06 (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 PIONEER substation, California 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.