- State has 3,000 deficient structures (08-03-07)
- KDOT to motorists: State's bridges are safe (08-03-07)
- Safety warnings began in 1990 (08-03-07)
- Questions emerge about safety of U.S. bridges (08-03-07)
- Quick checks urged for similar spans (08-03-07)
- Tragedy likely to reinforce bridge fears (08-03-07)
- DOT.gov: Federal Highway Administration list of old bridges by state
- IRE.org: National Bridge Inventory
- The history of the last major, sudden bridge collapse
- More information about the Minneapolis bridge
There's definitely a batch of bridges in Douglas County to keep a close eye on.
Kansas Department of Transportation leaders on Friday confirmed there are five bridges that have been rated as "structurally deficient," the same category that the collapsed Minneapolis bridge was rated.
Some of the Douglas County bridges are along the more heavily traveled routes in the county. KDOT leaders, though, were urging motorists to keep the rating in perspective.
"It means that we have to watch them closer," said Don Whisler, KDOT bridge management engineer. "It generally means they will be on a one-year inspection cycle instead of a two-year cycle. But it doesn't mean the bridges are unsafe."
The state bridges listed as structurally deficient are:
¢ Both underpasses at Sixth and Iowa streets that take motorists to and from the west Lawrence interchange for the Kansas Turnpike. Those two bridges both scored a 32 in a 100-point system. About 25,000 to 26,000 cars per day use the underpasses.
¢ The bridge on U.S. Highway 24/40 that crosses Mud Creek near Lawrence Municipal Airport. It scored a 58, and carries about 7,700 cars per day.
¢ The bridge on U.S. Highway 59 just north of the Wakarusa River. It scored a 21, and carries about 10,200 cars per day.
¢ The bridge along Highway 56 in west Baldwin City that crosses the east fork of Tauy Creek. That bridge had a rating of 11.5, the lowest in the county. It carries about 5,000 cars per day.
"That is not an unusual number of bridges for your type of area," Whisler said. "I would say that's probably a reasonable number for us to deal with."
'Definitely has problems'
The KDOT list is in addition to the two Kansas River bridges on the Kansas Turnpike near Lawrence. Structural issues already have caused engineers to schedule those massive bridges for replacement. The $140 million project is expected to begin next year.
KDOT leaders conceded that some of the bridges' scores were very low. With the Baldwin City bridge, which scored 11.5, it is hard to come to any other conclusion.
"That bridge definitely has problems," Whisler said.
But he said the score of a bridge is not a good way for the public to assess the chances of a bridge failing like the one in Minnesota. That's because only about half of the bridge's score is determined by structural issues. The other half of the score is related to whether the bridge is too narrow, the condition of the road leading to the bridge and other issues not related to its structural integrity.
"I think people should realize that you just don't run out and replace a bridge because it is called structurally deficient," said Keith Browning, Douglas County director of public works. "That's not what it means."
Two replacements in works
But the label does mean that engineers need to start considering future replacement or repair of the bridges. Two of the five state bridges are scheduled to be replaced, not including the Baldwin City bridge, which has the lowest score. Instead, the Mud Creek bridge and the U.S. Highway 59 bridge near the Wakarusa River are scheduled to be replaced in 2008.
Whisler said the state uses a complex system to evaluate which bridges should be replaced first. It factors in the bridge's sufficiency score, amount of traffic and detour options, among several other issues.
"What I can tell you is that we try to get the most bang for our buck and put the money where we need it most," Whisler said.
KDOT leaders on Friday weren't able to provide details on how much money they spend annually to replace bridges, or how many bridges per year they reasonably can replace.
They did say much of the money comes from the state's comprehensive transportation program. Before the comprehensive transportation program passed in the early 1990s, the state had 1,500 bridges that were deficient. Now, the number is 541.
Area bridges need help too
In addition to bridges on state roads, there are eight bridges on county and township roads that are rated as structurally deficient. One - along County Route 442 east of Eudora - is in the process of being replaced. Another - along East 100 Road near the Shawnee County line in southwest Douglas County - is scheduled to be bid for replacement in January. A third is the Kansas River bridge at Lecompton that is currently having its deck replaced.
The others are:
¢ A bridge on a small road serving two residences near North 900 and East 900 Roads near Lone Star.
¢ A 1920s-era bridge on a dead-end road near East 450 road north of Clinton Lake.
¢ A bridge southeast of Eudora near the Johnson County line.
¢ A bridge on North 1700 near the Shawnee County line.
¢ And the bridge that crosses the Wakarusa River on County Route 1057, between Eudora and Lawrence south of Kansas Highway 10.
Browning said that bridge is the largest bridge for which the county does not yet have a replacement plan. It likely will cost more than $2 million to replace, and could be significantly more if area planners want to use that road as part of a system to connect Highway 59 south of Lawrence with Kansas Highway 10 east of Lawrence.
In addition to the state and county bridges listed as structurally deficient, there are about 20 other bridges in the county that are listed as functionally obsolete. Those bridges don't have structural issues that could lead to a collapse, but they may have safety problems, such as being too narrow to carry traffic volumes.