By KERRY SMITH, EDITOR, ST. LOUIS CONSTRUCTION NEWS AND REVIEW MAGAZINE
The $278 million I-270 North Project – MoDOT’s largest project in 10 years that began construction in April 2020 – continues toward its December 2023 finish with major transportation infrastructural improvements in North St. Louis County.
I-270 North Project Director Justin Wolf says the large-scale effort will replace 12 highway bridges and build seven new ones, while adding a travel lane in each direction of I-270 from Lindbergh Blvd. to Missouri Route 367.
“This section of I-270 North was constructed in the 1960s,” said Wolf. “The bridges are reaching the end of their serviceable life. Now is the time to reconstruct with a modern design that will improve safety and reliability.”
Rebuilding the interchanges at Lindbergh Blvd., New Florissant Rd., Washington St./Elizabeth Ave., West Florissant Ave., New Halls Ferry Rd., Old Halls Ferry Rd and Route 367 are within the project scope.
In 2020, MoDOT and its design-build partners – which include Millstone Weber, Parsons Transportation Group, Horner & Shifrin, CBB, Terracon, Pace Construction and Excel Business Concepts – completed the new section of Pershall Road between New Florissant and Elizabeth, demolished the Old Halls Ferry Bridge over I-270 and opened a new bridge at that location, constructed the Bellefontaine Rd. roundabout, demolished the old Washington/Elizabeth bridge and built a new one at that site, completed the lane addition on southbound I-170 to eliminate an existing two-lane bottleneck section, performed major work at the new Lindbergh interchange and built the northbound Lindbergh bridge over I-270.
Upcoming 2021 work on I-270 North will include raising the grade on Dunn Rd. just west of Route 367 to tie into the new bridge, demolishing the old West Florissant bridge and building a replacement bridge there, starting work on southbound Lindbergh Ave. at I-270, and building the mainline and Pershall Rd. bridges over Coldwater Creek.
“Approximately 700,000 cubic yards of earthwork will be moved on this project,” Wolf said of the 44-month I-270 North rebuild. “Two large interchanges on either end of the 8-mile project require fill. The other interchanges being constructed in between have MSE (mechanically stabilized earth) walls at the bridge abutments. This will generate large amounts of excavation. Adding a lane in each direction on the interstate, reconstructing all of the outer roads and reconstructing five additional interchanges will generate the remaining fill material.”
Some 40,000 linear feet of storm sewer pipe and 500 drainage structures will be installed in total, according to Wolf, and 600,000 square yards of rock base for the roadways.
On average, more than 140,000 vehicles travel daily along I-270 North, making it one of the heaviest traveled roads in Missouri.