A 5.2-mile MetroLink light-rail extension to MidAmerica St. Louis Airport in Mascoutah, Ill., has been completed and is undergoing final safety and performance evaluations, with revenue service expected to begin in the coming weeks. The St. Clair County Transit District delivered the project using $127 million from the state's Rebuild Illinois capital program, the first MetroLink expansion in 20 years.

What does the extension change for riders?

The extension connects MidAmerica St. Louis Airport to the existing Shiloh-Scott station, adjacent to Scott Air Force Base. St. Clair County Transit District officials say the line establishes MetroLink as one of the few U.S. transit systems linking two major airports: MidAmerica St. Louis and St. Louis Lambert International.

Construction began in 2023. The project adds stations, park-and-ride facilities and supporting infrastructure along the 5.2-mile alignment in St. Clair County.

Who paid and who built it?

• State capital funding: $127 million from Rebuild Illinois
• Roadway improvements: $32 million in new road infrastructure
• Trail extension: $6 million for a 4.5-mile extension of the MetroBikeLink Trail
• Lead agency: St. Clair County Transit District

Illinois Governor JB Pritzker framed the project as an economic anchor for downstate Illinois. "From the beginning, I have worked with the General Assembly to prioritize rebuilding the downstate economy, and the MetroLink project has been a cornerstone of those efforts," Pritzker said. "With a total of $127 million in Rebuild Illinois investment, we've created jobs and business for local contractors and disadvantaged businesses while keeping project dollars moving through the regional economy."

How does this fit with other Illinois transit moves?

The airport extension is one piece of a broader downstate transit push by the Pritzker administration. In December, the governor signed the Northern Illinois Transit Authority Act, which created a new regional authority and committed $150 million in new annual operating revenue for downstate transit and infrastructure without raising statewide taxes.

This summer, IDOT-backed Warren County Public Transportation expanded into Henderson County, giving Illinois transit coverage in all 102 counties for the first time. On Sept. 30, IDOT announced $100 million in available funding for downstate transit capital projects.

What do local officials expect next?

St. Clair County Board Chair Mark Kern tied the line to broader economic development. "This new light-rail expansion supports existing business and will lead to new economic opportunities not only at MidAmerica St. Louis Airport, but throughout the entire county," Kern said. IDOT Secretary Gia Biagi pointed to longer-term benefits. "The MetroLink extension and surrounding improvements are positioning the region for success and a better quality of life for decades to come," Biagi said.

Lt. Governor Juliana Stratton emphasized statewide connectivity. "Whether you're traveling for work or recreation, this MetroLink Extension means you'll have more options with less stress," Stratton said.

When will trains start running?

Revenue service is anticipated to start in the coming weeks once final safety and performance evaluations wrap up. Biagi's IDOT and the St. Clair County Transit District will oversee the transition from construction to operations, with ridership data and on-time performance metrics likely to be tracked as the new segment enters service.

The completion positions MetroLink to test dual-airport connectivity at a time when state funding for downstate transit is rising through the $150 million annual operating stream and the $100 million capital pot announced Sept. 30.