Rebuilding Project for 138 kV Infrastructure Improvements – Longview Heights to Marshall Project

Project addresses potential overload of 69 kV line during outages of interconnecting lines

Longview Heights to Marshall Project
near Longview Texas
Client: American Electric Power

Sargent & Lundy EPC Joint Venture with EC Source Services

  • Public Outreach
  • Engineering and Design /Procurement
  • Construction, Testing, and Commissioning

The Longview Heights to Marshall Project near Longview, Tex., is being implemented to address potential overload of the existing 69-kV line during outages of interconnecting lines.

The overload issue will be resolved by rebuilding the transmission line from the Longview Heights substation to the Marshall substation.

  • Modifications at two substations (Longview Heights and Marshall)
  • Rebuilding 18 miles of 69kV line to 138kV
  • Distribution underbuild

The execution of this project was performed as a Joint Venture entity called ECSL.  Sargent & Lundy is providing the project management, public outreach support, procurement, and engineering & design for these projects. EC Source is providing the construction services.

The engineering work began in March 2016.  Construction started in October 2016 and complete March 2018.

Longview Heights to Marshall Project Profile PDF

For more information about our services, please visit our Power Transmission page.

For information about EC Source, go to

For information about American Electric Power, go to

Additional information on the Infrastructure Program projects:
69kV & 138kV Infrastructure Improvement Projects in Six States:  Project Profile

Todd Hanssen

Senior Vice President




Todd brings 25 years of experience in the design of power generation and transmission projects and is currently the director of power transmission construction services.