Work on the expansion of the Civic Center Transit Center is expected to begin next week, Bi-State Development said.
The Civic Center MetroLink Station in downtown St. Louis will remain open during the work.
MetroLink riders will be able to access the MetroLink platform from 14th and Spruce Streets, Bi-State said.
The north walkway from Clark Avenue to the station platform will be inaccessible during the first phase of the project. Construction fencing blocking the north walkway is scheduled to be installed the week of May 9.
In April, Bi-State held a groundbreaking ceremony for the 18-month project. The number of off-street bus bays will be tripled and a transit center building will be constructed on the site that and will include an indoor passenger waiting area, public restrooms, a concession area, digital boards with MetroBus arrival times, and a Metro Public Safety substation.
The cost of the project is $10.5 million project, with 80 percent coming from federal dollars, and with rest coming from local sales taxes, designated for transit, from the Missouri side of the Mississippi River.