ith
the recent collapse of the I-35W bridge between Minneapolis and
St. Paul over the Mississippi River, many people are wondering -
are the current bridges that span the Missouri River safe?
According
to the top engineer with the Nebraska Department of
Roads, the
answer is yes, even though three of the 17 bridges that allow
traffic to cross over the river are considered to be in
"poor" condition. Six bridges actually have lower
federal sufficiency ratings than the Twin Cities bridge but many
other factors go into considering a bridge structurally unsafe.
The U.S. Department of Transportation provides sufficiency ratings
through their National Bridge Inventory and uses the numbers
mainly to alert officials to begin repair or replacement planning.
These numbers are also used as benchmarks to qualify for federal
funding. The six Missouri River bridges in Nebraska with
rankings below 50 (which is the most recent rating given to the
Twin Cities bridge) are Rulo (48.6), Plattsmouth (22.9), Bellevue
(49.5), Veterans Memorial / South Omaha bridge (42.2), Decatur
(49.3) and Yankton (47.5). Rulo, Plattsmouth and Yankton bridges
had condition ratings of "poor" in at least one of three
criteria: deck, superstructure and substructure. Inspectors gave
the lowest rating to the Plattsmouth toll bridge which is
scheduled to be repaired next summer.The Rulo truss bridge
which was built in 1939 has been recently redecked. It was added
to the National Register of Historic Places in 1993 and was
featured in the movie Paper Moon.
A
new Yankton bridge is currently under construction. The estimated
completion date is sometime in 2009. A truss
bridge that crosses the river at Brownville, NE was labeled
"functionally obsolete" in 2006. It was built in 1939
and is now on the National Register of Historic Places. The term
"functionally obsolete" refers mainly to matters such as
width or lack of modern design standards. The Bellevue toll
bridge has been the subject of controversy for many years. It was
built in 1950
by the Bellevue Bridge Commission at a cost of $2.8 million. When
the initial bonds were paid off in 2000, no one wanted to own it
because of the cost it will take to make repairs. The Bridge
Commission is currently attempting to secure $1 million in bonds
for the repair work.
Although
listed on the National Register of Historic Places in 1992, the
Veterans Memorial Bridge (originally called the South Omaha
Bridge) is scheduled to be torn down and replaced with a new four
lane girder bridge. Opening of the new bridge is expected to be in
2010. In the meantime, Nebraska has placed a 5-ton vehicle limit
on the bridge.The Decatur bridge, which officially opened in
1956, was built on dry land in 1951. The Missouri River was
eventually rerouted to flow under the bridge. There are no former
plans in place to make repairs to this bridge. Over 70,000
bridges across the country are rated structurally deficient,
however, of the 10 worst counties for bridges in the nation, seven
are in Oklahoma and Nebraska. Nebraska Department of Roads does
have a policy of inspecting the Missouri River bridges every two
years so we should all feel confident that the recent tragedy in
the Twin Cities will not happen here.
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