ISO-NE transmission map: lines and substations
Explore public transmission lines and substations across the six New England states, alongside ISO-NE's load zones. Open the map to locate a site and inspect the infrastructure around it.
See it on the live ISO-NE map, updating as the market publishes.
Explore the ISO-NE transmission mapAbout this view
Locate ISO-NE transmission infrastructure
The map uses public HIFLD transmission-line and substation records across the six New England states. Inspect the published names, geometry and voltage fields where available, with ISO-NE's load 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 ISO-NE's load zones. It is geographic reference data — the operational network model, line ratings, and real-time flows stay with ISO-NE 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 ISO-NE'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 ISO-NE workspace with the same transmission, substation, and zone layers and the same viewport shown on this page.