Independence city officials say it will take about a year to replace a deficient culvert on 42nd Street between Noland and Phelps roads.
The city on Wednesday afternoon closed 42nd to through traffic at that point, about 500 feet east of Hocker Road, after a structural analysis report came back saying the culvert was failing enough that it couldn't be guaranteed to safely support traffic.
Before noon Thursday, someone had moved one of “Road Closed” signs and some drivers were ignoring the signs and driving across, though standing by one could observe an abnormal dip in the road right above the creek.
“It's the entire width of the roadway,” City Engineer Kati Horner said. “The material used for that culvert is corrugated metal pipe, and it's past its useful life.”
Rich Kemple, collection systems manager for the Water Pollution Control Department, said one-third of the city's 300 miles of storm pipe is corrugated metal, and the city does biannual inspections on its pipes and storm structures.
This particular culvert was inspected in November and generated enough concern that the city scheduled an engineer's structural analysis, which didn't happen immediately.
“It took about a week to generate that report,” Kemple said.
The culvert had been monitored and could well have been replaced in the near future, but the engineer's report moved such a project to the top of the list as an emergency, he said.
“When we find these issues, we try to categorize problems, attack the worst ones,” Kemple said. “The list always changes.”
So why will this new culvert take about a year, when nearby – some citizens pointed out – the new Phelps Road bridge over Interstate 70 went up in just several months?
When the Missouri Department of Transportation demolished the I-70 bridges last June, that came after a more than year of designing and planning the new bridges, bidding out the project and scheduling demolition. The 42nd Street culvert didn't allow such a timetable.
Normally, the project would have been designed and bid out before the city would need to close the road. In this case, the culvert failed well ahead of when the city anticipated putting it atop the project list.
“We've had a few rainy seasons,” Horner said, “and the way the water drains there has caused some erosion that contributed to the failure coming faster than expected.”
“Projects don't come together fast to start with.”
The project will be paid for with sales tax revenues.
“We'll replace it with other materials,” Horner said of the culvert. “Before that, we'll do fairly significant analysis with traffic on the road and water passing through during heavy periods.”