Interstate 270 and Interstate 170 Bridge Replacement in St. Louis

When will construction begin?

Construction will begin in the spring of 2025. The project is expected to be completed by December 2025.

What is the cost of this project?

This project will cost between $4 and $5 million.

What construction impacts can drivers expect?

The ramp from eastbound I-270 to southbound I-170 will be closed during construction. Pershall Rd. will be closed for one weekend for bridge demolition. After that, Pershall Rd. will remain open at all times except for brief periods for construction equipment movement and setting girders for the new bridge.

After construction is completed, the ramp will open to traffic and traffic patterns returned to normal.

What is the expected detour?

The signed detour will be as shown below. The detour will use the recently constructed U-turn ramp just west of New Florissant. This is a free-flowing detour with only one brief stop at the north outer road, then back on I-270 to use the westbound I-270 ramp to access southbound I-170.