Substation upgrades and new power line will strengthen grid and support future energy needs
GRANITE CITY, Ill. (October 15, 2026) – Ameren Illinois crews have begun work on a series of electric infrastructure upgrades in the Granite City area designed to strengthen reliability and improve overall system performance for customers.
A major component of the project includes construction of a new switching station near the U.S. Steel facility, upgrades to two existing substations and installation of a new 69-kilovolt subtransmission line. Additional electric line projects will also be completed as part of the overall effort to modernize and strengthen the local electric system.
The improvements are designed to increase system resiliency, provide greater operational flexibility and reduce the frequency and duration of outages for residential, commercial and industrial customers in the Granite City area. Construction is expected to continue through November 2027.
These upgrades will also help strengthen the local electric grid amid increasing severe weather events. Illinois is currently the nation's most active state for confirmed tornadoes and experiences severe weather in all seasons. By modernizing critical infrastructure and creating additional pathways to restore power, these improvements will enable crews to respond more efficiently when storms impact the region.
"Investments like these are essential to maintaining a reliable and resilient electric system for our customers," said Langston Rose, director of West Region electric operations for Ameren Illinois. "In addition to supporting future energy needs, these upgrades will strengthen the local grid and help us better withstand and recover from severe weather events that can affect communities throughout the Metro East."
The new switching station will provide additional flexibility in managing power flows throughout the area, while the substation and subtransmission line enhancements will create a more robust electric network capable of supporting current and future demand.
The Granite City project is part of Ameren Illinois' ongoing commitment to investing in infrastructure that enhances reliability, strengthens resilience against severe weather and delivers long-term value to customers. The upgrades reflect years of planning and are designed to support the current and future energy needs of homes, businesses and industries throughout the region.
About Ameren Illinois
Ameren Illinois delivers energy to 1.2 million electric and more than 800,000 natural gas customers throughout central and southern Illinois. Our service territory covers more than 1,200 communities and 43,700 square miles and our mission is to power the quality of life. For more information, visit AmerenIllinois.com. Follow us at @AmerenIllinois or Facebook.com/AmerenIllinois.