Pinal Central to Tortolita Transmission Line

Tucson Electric Power is building a new 500 kilovolt transmission line in Pinal County with a goal of boosting electric reliability in Southern Arizona.

The line extends approximately 41 miles from Southeast Valley Project’s Pinal Central Substation east of Casa Grande to TEP’s Tortolita Substation southeast of the Red Rock area. When finished in December 2015, it will expand access to renewable energy projects and meet future energy demands in the Tucson metropolitan area and surrounding region.

The transmission line route, most of which passes though Arizona State Trust land, was identified after TEP conducted public outreach meetings and natural, cultural and visual resource studies as part of its line-siting process that began in 2008.

TEP mailed newsletters to thousands of landowners and residents in the project area, held public open houses and spoke with neighbors, jurisdictional representatives and other stakeholders before it received approval from the Arizona Corporation Commission in 2012 to build the line.

TEP designed the project to minimize disturbance of native vegetation, wildlife and cultural resources.

Route planners used 3-D modeling to identify saguaro that could grow close to power lines over the next 20 years and cause an outage. Many of these saguaros — and small cacti that were in the construction path — were safely transplanted away from the project area in a joint effort between TEP and the Tucson Cactus and Succulent Society.

The cacti serve as habitats and food sources for a wide variety of desert wildlife, including the lesser long-nosed bat, which depends on saguaros for food.

“We’re dedicated to preserving the environment and want to minimize our footprint during the construction of this line,” said Christina Frazer, Senior Project Manager with TEP.

All construction workers were provided environmental training to ensure that best management practices were followed throughout the project.

“It’s important for us as a company to manage the land in a responsible way while providing quality service to our customers,” said Leslie Carpenter, a TEP Environmental & Land Use Planner II.

For construction updates and a detailed route map, visit the project webpage on

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