Ground was broken Thursday on the new Daniel Boone Bridge just west of Chesterfield.
The $111 million project will replace a 75-year-old span over the Missouri River and link St. Louis and St. Charles Counties.
MoDOT District Engineer Ed Hassinger says the bridge is the final project to make I-64 a true, interstate-quality, highway.
Representatives for Ameristar Casino say they will file a lawsuit Tuesday morning to block a November ballot question on whether or not to ban smoking in St Charles County.
According to casino representatives, if passed, the ban could put it at a disadvantage because patrons at other casinos in the state can light up when they gamble.
St. Louis Public Radio is a service of the University of Missouri-St. Louis.