SPP transmission map: lines and substations
Explore public transmission lines and substations across the Southwest Power Pool footprint, alongside the mapped market zones. Open the map to locate a site and inspect the infrastructure around it.
See it on the live SPP map, updating as the market publishes.
Explore the SPP transmission mapAbout this view
Locate SPP transmission infrastructure
The map uses public HIFLD transmission-line and substation records across the Southwest Power Pool footprint. Inspect the published names, geometry and voltage fields where available, with the mapped market zones for orientation.
Put a site in its grid context
Use the map to compare a site with nearby substations, lines and other available layers. The public inventory describes infrastructure geography; proximity to a line does not establish a connection point, available capacity or an approved interconnection.
Questions
What does this map show?
The transmission lines and substations published in the HIFLD public inventory, drawn across the SPP footprint. It is geographic reference data — the operational network model, line ratings, and real-time flows stay with SPP and the transmission owners.
Can I tell from the map where a project can interconnect?
It shows where the public network geography runs, which is the starting point. Whether a specific point of interconnection works is settled by SPP's interconnection studies and the transmission owner.
Can I inspect the underlying public data?
Yes. The linked Ask the Grid catalog page documents the HIFLD transmission-line source, schema, and coverage.
Will the map open with these layers?
Yes. It opens the live SPP workspace with the same transmission, substation, and zone layers and the same viewport shown on this page.