Bridge's crash into river provides surprise ending

A demolition blast Thursday tore apart the old Mississippi River bridge at Cape Girardeau, doing more damage than expected and leaving wreckage scattered across the river like the backdrop of a disaster movie.

It wasn't supposed to happen that way. Still, state and federal officials said the wreckage in the main navigation channel should be hauled from the river in time for barge traffic to resume this morning as originally planned.

The demolition blast -- its numerous explosive charges sounding like a cannon and shooting up black clouds of smoke -- dropped the 671-foot-long span nearest the Missouri shore into the river as planned.

But the blast also set up a chain reaction that damaged the other remaining spans of the bridge. The blast caused the other 671-foot section of the main span to jackknife into the river, tearing out part of a concrete pier and sending one end of the remaining 314-foot span crashing into the water.

The blast shortly before 7 a.m. left hundreds of spectators, the demolition contractor and city, state and federal officials guessing about what went wrong.

"It may have been the vibration from the blast," said Stan Johnson, Missouri Department of Transportation engineer. "Something happened to put more stress on the bottom beam of the second span and it failed."

Demolition contractor Scott Gustafson, president of Dem Tech of Dubois, Wyo., was surprised by the added destruction.

"I have never seen another steel span fail," said Gustafson, who has demolished hundreds of structures with military-grade explosives.

"The charges had nothing to do with it," he said of the two other spans collapsing.

Gustafson's company used 327 charges -- 62 pounds of explosives -- to blow up the main span.

As for the damaged concrete pier, Gustafson said it had little in the way of steel supports in it unlike today's concrete structures. That may have contributed to part of the pier falling into the river when the second bridge span buckled, he said.

The fact that the main span near the Missouri shore and the second large span were actually built as part of a single steel truss may also have contributed to the failure, MoDOT officials and Gustafson said.

"It failed and it was a domino effect," Gustafson said.

The $2.23 million demolition of the 76-year-old bridge began with a demolition of some of the Illinois approach spans on Aug. 3. A blast on Aug. 26 took down another 314-foot span, leaving only three spans standing.

All of the spans were scheduled to be demolished by the middle of this month. Thursday's blast just hurried the process along, Johnson said.

KFVS12 reporter C.J. Cassidy was originally set to push the button sparking the demolition charges. Last year, she won a drawing for the honor. But Cassidy recently decided she wanted to wait until the next blast so her father, who was out of the country, could attend.

Now there may not be another blast. But MoDOT spokeswoman Tonya Wells said it was probably just as well Cassidy didn't set off Thursday's blast.

"I am sure she is glad she wasn't the one that pushed the button," Wells said.

Spectators -- many of whom gathered along the breezy, riverfront more than an hour before the blast -- were awed by the destruction.

"We have been approving and witnessing bridge demolitions for 25 years and I have never seen anything like that," said Roger Wiebusch, bridge administrator for the U.S. Coast Guard in St. Louis.

Wiebusch said the added destruction shouldn't pose a problem to barge and boat traffic. As planned, the Coast Guard closed the river at Cape Girardeau to all boat and barge traffic for 24 hours to allow barge cranes to remove the debris of the exploded first span from the navigation channel.

The added destruction shouldn't slow down that timetable, he said. Wiebusch said the general contractor, Midwest Foundation Corp. of Tremont, Ill., should have the steel removed from the river by 8 a.m. today.

Crews on crane barges began removing the debris soon after the blast.

Wiebusch said the broken pier is resting on the bottom of the river bed and shouldn't hinder barge traffic or passenger boats.

The River Explorer passenger barge was scheduled to dock at Cape Girardeau Thursday evening on its southbound journey. The barge is expected to resume its southbound journey at noon today, passing through an area of the river where steel blocked the route only a day earlier.

MoDOT's Johnson said officials and the contractor were still deciding on how best to remove the remaining damaged spans and whether more blasts will be needed. Those plans then will need approval from the Coast Guard.

The Coast Guard's Wiebusch doesn't expect his agency to formally investigate Thursday's blast. He said there is no evidence that the demolition company and its crew was negligent in how it exploded the span.

"We deal with them a lot," Wiebusch said. "They have a proven track record of success."

City, state and federal officials said the unexpected bridge damage underscored the importance of having an evacuate zone as was done in advance for this blast.

Cape Girardeau police required people to either evacuate their homes and businesses within a 1,500-foot radius of the blast or stay inside their buildings during the blast.

The demolition was scheduled for 6:30 a.m., but was delayed by nearly half an hour because some spectators in the evacuation zone initially resisted instructions from police to leave the area or move indoors, city police chief Steve Strong said.

Officials said the blast didn't damage any downtown buildings or injury anyone.

"I don't know what we could have done differently," Johnson said. "It is one of those unforeseen things that happen. Luckily the unforeseen thing happened out in the river."

mbliss@semissourian.com

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