The Blanchette Missouri River Bridge is undergoing a $35 million major rehabilitation.
The Blanchette Missouri River Bridge is undergoing a major rehabilitation that has restricted the five-lane eastbound bridge to just two lanes. The $35 million project is necessary due to the age of the bridge, which opened in 1978. The last repairs were completed in 2006.
"It was built in the early ‘70s," said Andy Tuerck, St. Charles area engineer of the Missouri Department of Transportation (MoDOT). "It needs a major rehab about every 20 years. The biggest component is paint replacement. I make the analogy, ‘You can put a layer of shingles on top of your old shingles when you have hail damage. But you can't just keep adding shingles.' Likewise, you can't keep adding paint. You can't just keep layering it up and layering it up. It doesn't end up protecting the steel."
According to the MoDOT project website, the agency regularly inspects its bridges and when concerns are found, they are monitored and, if necessary, repaired.
"We found moderate deteriorating elements, including moderate cracking and splitting on the eastbound portion of the Blanchette Bridge. Painting also provides corrosion protection. The paint system on the bridge has also reached the end of its life. If nothing is done now, the bridge will continue to deteriorate and more costly repairs or a complete bridge replacement will be necessary in the future. Doing this work now protects Missourian's investment in this bridge and ensures it will provide many more years of reliable service."
There are at least six paint crews with local contractor KCI at work daily on the half-mile long bridge. Their job is made somewhat easier by the "safe span," an underside or secondary bridge that makes barges and manlifts unnecessary.
While the most significant work is painting — including 16 spans of steel plate girders — the project also calls for the replacement of expansion joints, which Tuerck noted "take a beating," and the encapsulation of barrier walls.
"They're making it thicker and taller," Tuerck said. "They came up with an innovative use of shotcrete. They shoot out a really dry mix of cement, sand and water with a Schwing concrete pump. It's super dry and they can shape it."
The biggest challenge has been traffic, but crews are finding the silver lining in COVID-19.
"The bridge usually sees over 100,000 vehicles per day," Tuerck said. "Full-time lane restrictions really cause backs up. We've seen a 30 percent drop in traffic so that has really helped us with the back up."
Equipment on the job includes compressors and reclaiming units to capture paint flecks, which are lead-based.
The project also has occasional impacts to the popular Katy Trail, a gravel path used by cyclists and pedestrians that follows an old railroad bed. Crews will need to cross the trail to move equipment and materials to and from the job site. There also is work to the bridge that needs to be done next to or directly above the trail. MoDOT will work to minimize the impacts to the trail, but may need to close it for short periods of time.
The westbound bridge was last rehabilitated in 2012. The eastbound bridge project is scheduled for completion in November 2021. CEG