Substation-Adjacent Datacenter Sites in Iowa
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 Iowa
| Site | Type | County | Voltage | Capacity | Queue wait | Score |
|---|---|---|---|---|---|---|
| WALTER SCOTT ENERGY CENTER | Substation-Adjacent | Mills County | 345 kV | 600 MW | 4.3 yrs | 70.2 |
| UNKNOWN130427 | Substation-Adjacent | Dakota County | 345 kV | 600 MW | 4.3 yrs | 69.9 |
| BONDURANT | Substation-Adjacent | Polk County | 345 kV | 600 MW | 4.3 yrs | 69.3 |
| GREATER DES MOINES ENERGY CENTER | Substation-Adjacent | Polk County | 345 kV | 600 MW | 4.3 yrs | 69.1 |
| UNKNOWN131416 | Substation-Adjacent | Mills County | 345 kV | 600 MW | 4.3 yrs | 69.0 |
| SE POLK | Substation-Adjacent | Polk County | 345 kV | 600 MW | 4.3 yrs | 69.0 |
| UNKNOWN137755 | Substation-Adjacent | Mills County | 345 kV | 600 MW | 4.3 yrs | 69.0 |
| UNKNOWN131382 | Substation-Adjacent | Scott County | 345 kV | 600 MW | 4.3 yrs | 68.2 |
| TIFFIN | Substation-Adjacent | Johnson County | 345 kV | 600 MW | 4.3 yrs | 68.1 |
| GRIMES | Substation-Adjacent | Dallas County | 345 kV | 600 MW | 4.3 yrs | 68.1 |
| SYCAMORE | Substation-Adjacent | Polk County | 345 kV | 600 MW | 4.3 yrs | 68.0 |
| SIOUX CITY | Substation-Adjacent | Plymouth County | 345 kV | 600 MW | 4.3 yrs | 68.0 |
| BLACK HAWK | Substation-Adjacent | Black Hawk County | 345 kV | 600 MW | 4.3 yrs | 67.8 |
| UNKNOWN131604 | Substation-Adjacent | Scott County | 345 kV | 600 MW | 4.3 yrs | 67.7 |
| SUB 91 | Substation-Adjacent | Scott County | 345 kV | 600 MW | 4.3 yrs | 67.6 |
| UNKNOWN131605 | Substation-Adjacent | Rock Island County | 345 kV | 600 MW | 4.3 yrs | 67.3 |
| HILLS | Substation-Adjacent | Johnson County | 345 kV | 600 MW | 4.3 yrs | 67.2 |
| ARNOLD | Substation-Adjacent | Linn County | 345 kV | 600 MW | 4.3 yrs | 67.0 |
| NORWALK | Substation-Adjacent | Warren County | 345 kV | 600 MW | 4.3 yrs | 66.9 |
| HAZLETON | Substation-Adjacent | Buchanan County | 345 kV | 600 MW | 4.3 yrs | 66.7 |
| BOONEVILLE | Substation-Adjacent | Madison County | 345 kV | 600 MW | 4.3 yrs | 66.5 |
| ROCK CREEK | Substation-Adjacent | Clinton County | 345 kV | 600 MW | 4.3 yrs | 65.9 |
| RAUN | Substation-Adjacent | Dakota County | 345 kV | 600 MW | 4.3 yrs | 65.9 |
| UNKNOWN130433 | Substation-Adjacent | Dakota County | 345 kV | 600 MW | 4.3 yrs | 65.7 |
| O'BRIEN | Substation-Adjacent | O'Brien County | 345 kV | 600 MW | 4.3 yrs | 65.6 |
How does Iowa compare with other states for substation-adjacent sites?
With 761 sites, Iowa ranks 24th 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, Iowa averages 56.3, the 8th-highest of 52 states, and its candidate sites face an average interconnection-queue wait of 4.3 years.
Where are the highest-scoring substation-adjacent sites in Iowa?
The top 25 range from 70.2 to 65.6 on the 0–100 DC Readiness Score. They are concentrated in Polk County (4), Mills County (3), Dakota County (3) and Scott County (3). By grid region, 25 are in MISO.
County pages: Polk County · Mills County · Dakota County · Scott County
What power, fiber and flood exposure do these substation-adjacent sites have?
Of the top 25 substation-adjacent sites in Iowa, 25 have a recorded nearest-substation voltage, with a median of 345 kV; for 25 that substation is rated 230 kV or higher. Their counties have a median of 14 fixed fiber broadband providers in FCC data. The median distance to the nearest internet exchange facility is 14 km. The median interconnection-queue wait in their markets is 4.3 years. None of the 7 with a mapped FEMA flood zone sits in a high-risk (A or V) zone. 3 lie within 25 km of a binding transmission constraint.
Frequently asked questions
How many substation-adjacent datacenter sites are in Iowa?
GridCensus catalogs 761 substation-adjacent datacenter candidate sites in Iowa, 2% of the national total for this type (24th 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 Iowa?
By DC Readiness Score, WALTER SCOTT ENERGY CENTER in Mills County ranks first at 70.2/100, followed by UNKNOWN130427 in Dakota County at 69.9.
Which Iowa counties have the best substation-adjacent sites?
The top 25 substation-adjacent sites in Iowa are concentrated in Polk County (4), Mills County (3), Dakota County (3) and Scott County (3).
How does Iowa score for datacenters overall?
All 2,572 scored sites in Iowa average 56.3/100 DC Readiness, the 8th-highest of 52 states, against a national average of 53.0.
More on substation-adjacent sites and Iowa
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 Washington· 1,343 sites
- Substation-Adjacent sites in Minnesota· 1,270 sites
- Substation-Adjacent sites in Kentucky· 1,261 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 Iowa”, https://gridcensus.com/site-types/substation/iowa (data as of November 12, 2026).
Go deeper than the public screen
Every site and score for Substation-Adjacent sites in Iowa 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.