Latest News: June 28, 2019

Current construction work zones map

The map above displays the current and completed work areas for the Thornton Substation Project. Click on the map to see a larger version.

The Thornton Substation will be energized by the end of July 2019 (in time for summer peak usage) and project construction is anticipated to be complete in the third or fourth quarter of 2019.

In the coming months, crews will work on the following activities to complete construction:

  • Installing permanent gates at the substation entrances.
  • Constructing the right turn lane from northbound Holly Street onto East 119th Avenue.
  • Installing landscaping at the substation site.
  • Restoring the substation site to conditions required by permits.

Crews have completed installation of the new overhead-to-underground transition structures and construction associated with the underground transmission line in East 112th Avenue and Holly Street and are currently working on restoration in this area.

We thank the community for your continued patience during the construction of the project.

Public safety is at the foundation of all we do. It's our mission to ensure your family, neighbors, and every one of our employees stay safe each day. Xcel Energy is committed to continuing to maintain safe construction work zones and motorist and pedestrian detours as dictated by our traffic control plans that are reviewed and approved by the City of Thornton. Please use caution when walking or driving near construction zones, and refrain from entering construction work areas.

Please be mindful of current construction conditions and traffic control measures, as they are likely to change based upon construction progress. Please help us maintain a safe community environment by participating in safe practices near our construction work zones:

This webpage will be updated as additional information regarding construction activities is available.

If you have any questions or concerns about our construction, please email us at or call our project hotline at 844-551-6281. To receive email updates, subscribe to the Thornton Substation email list.

Please note that construction schedules are subject to change.

Project Schedule

Please note that the project schedule is subject to change.

  • Fourth Quarter 2017: Installation of security fencing and demolition of existing structures at the substation site
  • Second Quarter 2018: Grading activities to begin
  • Second Quarter through Fourth Quarter 2018: Underground transmission line construction
  • Second Quarter 2018 through First Quarter 2019: Wall and foundation construction
  • Fourth Quarter 2018 through First Quarter 2019: Underground transmission line cable installation
  • Fourth Quarter 2018 through Third Quarter 2019: Substation electrical equipment installation and testing
  • Mid-2019: Substation construction complete and in-service
  • Third Quarter through Fourth Quarter 2019: Installation of landscaping