Grid United is developing Three Corners Connector. Grid United is an independent transmission company developing the infrastructure needed to create a more resilient and efficient electric system to the benefit of all consumers.
Three Corners Connector is anticipated to be 300 miles long, extending from an existing substation in Pueblo, Colorado, to a proposed substation near Guymon, Oklahoma. Converter stations will be constructed near each endpoint to convert the transported energy between alternating and direct current.
Using community and stakeholder feedback, Three Corners Connector will finalize the route analysis and initiate regulatory filings, with final approvals expected in 2026. The route will remain “proposed” until it receives approval from county, state, and federal regulatory bodies.
By connecting the two largest electric grids in the United States, Three Corners Connector will strengthen the United States’ electric transmission grid to create a more reliable and efficient electric system that takes advantage of the nation’s abundant and geographically dispersed natural resources to benefit all consumers.
Numerous studies by the U.S. Department of Energy (DOE) and other government and nongovernmental organizations have demonstrated a need for long-distance transmission projects, including high-voltage direct current transmission lines like Three Corners Connector.
Yes, a small portion of the proposed route (less than 9%) is on public lands. The rest is on private lands.
Three Corners Connector benefits both customers and power producers in Colorado and Oklahoma. Benefits include:
HVDC technology is the most efficient way to transport electricity over long distances. For more details on HVDC technology and its benefits, click here.
By utilizing direct current (DC) technology, Three Corners Connector can send electricity in either direction, east or west. Three Corners Connector can serve to balance the electricity needs in the Western and Eastern Interconnections by transporting electricity when and where it is needed.
The Three Corners Connector project team is actively engaging with stakeholders along the route. Additionally, there will be opportunities for public input during the permit approval processes. If you would like to get in touch with the Three Corners Connector project team, please reach out to info@threecornersconnector.com.
Yes. We have purchased easements, but the land still belongs to the existing landowners and can be utilized for activities such as farming, grazing cattle, and other activities that do not interfere with the operation of the line.
Wherever feasible, the proposed route follows property lines or existing infrastructure. Land agents worked with landowners on route placement during the landowner consultation phase.
The project acquired a 200-foot right-of-way from landowners along the proposed route. Additionally, the project will acquire Additional Temporary Workspace as needed for construction.
Construction typically involves the following:
Construction for Three Corners Connector will take approximately three years. Certain land use practices will be restricted while construction is taking place on your land such as excavations or topographic changes. When construction is complete, we will restore the easement area to its original condition and appearance, at which point landowners can resume normal use with a few exceptions, laid out in the executed Easement Agreement.
Please watch this video for additional information on the transmission line construction process.
All restoration activities will be coordinated with appropriate landowners. Restoration can include replacing topsoil and reseeding to bring areas of land disturbed during construction back to their normal contour. Any topsoil that is removed during construction would be stored then used during site restoration after construction work is completed.
Construction and maintenance of the towers and converter sites require a combination of temporary and permanent access roads. Landowners are consulted about access road placement on their property.
Construction crews will aim to access the right-of-way from public roads that intersect or are adjacent to the right-of-way. Once an access road is established, construction will follow the right-of-way to the next access road location, which will preferably be located at the next public road crossing. In some instances, depending on the land’s topography or other environmental conditions, off-right-of-way access may be needed to construct or maintain the line.
Three Corners Connector is currently coordinating with local, state, and federal permitting authorities and will continue to do so over the course of the project’s development.
Multiple permits and approvals are required prior to beginning construction, including state regulatory approvals, land use permits, highway crossing permits, and construction stormwater permits.
Special Use Permit (SUP)
A special use permit is a type of zoning authorization that requires a detailed review by the county to confirm compatibility with county zoning and land use planning objectives before the activity can proceed. This involves reviewing how the project might fit within the county’s development plans or affect nearby properties and the environment.
Area and Activities of State Interest (1041) Permit
Similar to a local zoning and land use management process, the 1041 process is a local permitting authority, which allows for local governments to review a propose local development and evaluate its land use and the associated economic, environmental, and community footprint.
Oklahoma Corporation Commission – Certificate of Authority (COA)
Oklahoma requires a Certificate of Authority (COA) from the Oklahoma Corporation Commission before construction can begin. The COA process ensures appropriate notice, transparency, and public engagement.
Key steps include:
This process runs in parallel with other coordination in Oklahoma, including work related to landowner outreach and local engagement requirements.
Endangered Species Act (Section 7 or 10 Consultation)
By reviewing a project’s potential to affect listed endangered or threatened species, US Fish and Wildlife may identify certain conservation measures to protect sensitive habitats and reduce the potential for direct or indirect effects to a listed species.
Clean Water Act Section 404 – Nationwide Permit 57 Electric Utility Line and Telecommunications Activities
US Army Corps of Engineers authorization is required for construction activities that result in filling or dredging within waters or wetlands. The authorization process involves strict rules to protect water resources and to ensure activities do not result in impacts to water quality. For projects like Three Corners Connector, there is a specific type of permit (Nationwide Permit 57) that allows limited impacts for the construction and operation of a transmission line.
Developing America's Next-Generation Infrastructure to Power Our Future.
Grid United is developing Three Corners Connector.
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