Del Sol - FronteraTransmission Improvements Project


Following Texas’ winter storms in February 2021, the Public Utility Commission of Texas (PUC) and Electric Reliability Council of Texas (ERCOT) identified the need for additional transmission lines in the Rio Grande Valley.

As part of the larger RGV Reliability Improvements Project, AEP Texas and ETT representatives are partnering to engineer and construct the Del Sol – Frontera Transmission Improvements Project to strengthen the electric grid and help withstand weather impacts.

The project involves building approximately 36 miles of double-circuit 345-kilovolt (kV) transmission line from ETT'S Del Sol Substation, located near Rio Grande City, to AEP Texas' Frontera Substation, located in Mission.

The Del Sol to Frontera Transmission Improvements Project will improve regional reliability and resiliency by:

  • Helping strengthen the power grid against severe weather events.
  • Reducing the likelihood and duration of wide, community-sustained outages.
  • Providing additional capacity for growth and economic development.

Company representatives will reference public input to make necessary adjustments to the potential route links. The PUC will review the preliminary route links and consider public feedback before identifying a final route for the Del Sol - Frontera Transmission Improvements Project. Representatives accepted comments on the proposed route links through November 15, 2022, with multiple opportunities for in-person open houses in October 2022. Feedback was also accepted through the website feedback form, email, phone or mail.

Project Updates

Public open houses were hosted in October 2022 in which project team members were available to review maps and answer any questions. 

Regulatory Updates

June 2023: Company representatives filed a Certificate of Convenience and Necessity (CCN) with the Public Utility Commission of Texas (PUC) following a review of public input on route link development and additional route analysis on June 5, 2023.

September 2023: The PUC approved the project and line route on September 28, 2023. View the PUC final order here.


Project Timeline



The project includes AEP’s BOLD (Breakthrough in Overhead Line Design) technology, which are capable of operating more efficiently than conventional transmission pole designs.

  • Typical Height: 140 feet*
  • Typical Distance Between Structures: Approximately 1,000 feet*
  • Typical Right-of-Way Width: 150 feet*

*Exact structure type, heights, right-of-way widths and spacing may vary based on location

The current route links run through Starr and Hidalgo counties in Texas. Multiple potential route links will be presented to determine the final proposed routes prior to CCN filing. The companies will not build all route links; rather, they will provide multiple recommendations for the PUC to identify the final route. This could include a combination of the proposed route links that connect from Del Sol Substation to the Frontera Substation.

AEP Texas and ETT implement a comprehensive siting process that strikes a balance between building infrastructure and respecting land use and the environment. Both companies incorporate and review public input along with the following factors:

  • Existing land use
  • Public lands: state, federal, and military lands
  • Conservation lands and local parks
  • Sensitive species and habitats
  • Soils and topography
  • Historic and cultural resources
  • Existing infrastructure

Similar to other linear infrastructure projects, AEP Texas’ and ETT’s right-of-way representatives work directly with landowners to obtain the necessary land rights for the project once the PUC determines the final route.

Right-of-way agents work with landowners on the details of easements to reduce impacts on farming practices and personal land use. There also can be compensation for crop loss or damages during construction, which will be handled during one-on-one discussions with involved landowners.

AEP Texas and ETT treat people and the environment with respect in constructing new facilities. We believe property owners should be treated fairly and made whole for property encumbered by a transmission line project.

We prioritize:

  • Proactive and early engagement with landowners and stakeholders
  • Transparent proceedings throughout the project
  • Maintaining a positive working relationship with all regulatory and environmental agencies

Project Maps

Please note that these maps are preliminary and do not reflect any final power line route decisions.


Step 1: Below is an Overview Map that displays the entire project area. Please use the Overview Map to find the general location of your property.


Virtual Open House Project Fact Sheet Access Roads Field Activities

AEP Texas serves over one million consumers in the deregulated Texas retail electric marketplace.

* Required field. By clicking submit, you agree to AEP's Privacy Policy.

Paper plane

Your message has been sent! We'll be in touch shortly.