Four bridges in Missouri are already closed because of their deteriorating condition, and one Transportation Department official says more will close in the coming year.

The Route H bridge over the Cuivre River in Lincoln County (photo courtesy; the Missouri Department of Transportation)

The Route H bridge over the Cuivre River in Lincoln County is still open but has a 10-ton weight limit; too low to allow a school bus full of children.   (photo courtesy; the Missouri Department of Transportation)

Based on the latest round of inspections there are 641 bridges in Missouri considered to be in the worst condition possible before they must be closed, while having no funds targeted at their repair or replacement. That’s an increase of 50 bridges from last year.

State Bridge Engineer Dennis Heckman says most bridges are built to last 50 years but those 641 are generally between 60 and 85 years old.

“They’re spread all across the state,” Heckman told Missourinet. “They’re in rural areas, they’re in urban areas, some are over streams, some are overpasses, some are over railroads. Just every kind of bridge you can think of. They’re all just getting too old.”

Heckman said knowing which of those will be the next to close is difficult to predict.

“If a really heavy load goes across a bridge, gets overloaded, you never know how that’s going to go,” said Heckman. “I’m not saying these 640 are going to close in the next year, but there’s going to be some, that’s for sure.”

Pressed to offer a guess how many, Heckman said his boss asked him to make a similar projection as part of a discussion about public safety.

“Anywhere from one to fifteen would be a guess,” said Heckman, adding that would be on top of the four already closed.

MODOT map of bridges with weight restrictions due to diminished condition

MODOT map or bridges listed in “critical” condition

He said like most issues facing the Transportation Department, this is one of funding.

“There hasn’t been a tax increase for transportation since the late 90s, and everybody gets better gas mileage, and of course when you throw inflation in there we just don’t have the purchasing power we used to have,” said Heckman.

The department said of its 10,376 bridges on state highways, some 50 to 100 get added to the list of those in “critical condition” each year. That is based on a federal rating scale in which a bridge rated a “9” is in the best condition and one rated a “2” is closed. A “1” rating is given to a bridge that has collapsed.

Heckman said the bridges on the “critical” list rank a “3” or “4.”

To get caught up in bridge repair and replacement, Heckman said the Department would need to be working on about 100 bridges a year. With current funding levels it is only working on about 30 a year.

He said in deciding which 30 to work on, MODOT relies on input from local officials.

“We look at thinks like detour length, daily traffic, we even get down to the level of looking at are we splitting a school district, are you right in the middle of an ambulance or fire district,” said Heckman.

Heckman said inspections of bridges will continue and said those bridges that remain open to traffic are safe.