SPANNING THE MISSISSIPPI: AT $90 MILLION, RIVER BRIDGE FAR EXCEEDS COST OF 1927 SPAN

In 1927, the Cape Girardeau traffic bridge across the Mississippi River took 17 months to build and cost $1.6 million.

The Bill Emerson Memorial Bridge will take more than four years to build and will cost an estimated $90 million.

In today's dollars, the old bridge would have cost $14.7 million -- still a far cry from the cost of the new one. Why does the new bridge take so much longer to build, and why is it so much more expensive?

There are basically three reasons, said Randy Hitt, area engineer for the Missouri Department of Transportation, and Matt Girard, project manager for Flatiron Structures Co. LLC, which is building the bridge.

The new bridge is bigger. It is designed to withstand an earthquake of 8.0 on the Richter scale, and construction has followed complex governmental regulations.

The result is a bridge that takes longer to build and costs more.

"But in the end we have a much better bridge," said Girard.

Bigger

The center span of the new bridge is 1,150 feet, almost double the 671-foot span between piers of the existing bridge.

The longer center span added considerably to the complexity and cost of the new bridge, Gerard said.

The center pier of the new bridge isn't in the middle of the river navigation channel, making river traffic safer.

"To get that longer span we have a much more expensive bridge," Girard said..

In fact, the long center span required a different type of bridge. The new bridge is a cable-stay bridge; the old one a truss bridge. The cable-stay bridge is more expensive to construct.

In addition, the new bridge will be about five times as wide as the old bridge.

The old bridge is about 20 feet wide from railing to railing with two lanes of traffic. The new four-lane bridge will have 80 feet of driving space plus shoulders. It will be about 100 feet from railing to railing.

Seismic design

In 1927, very few structures were designed with earthquakes in mind. In 1997, seismic design of structures in Southeast Missouri is a must.

"The bridge is heavier and beefier, and that adds cost and time," he said.

For example, all the piers are linked to 8 feet of bedrock. Some fissures were discovered in the rock at the center pier in the river. Within the next few weeks, the fissures will be filled with a cement mixture.

"It's kind of like filling a cavity in a tooth," Hitt said.

But the cavity is under the river and can't be seen, explained Girard.

The seismic features include a lot of reinforcing steel and lateral support in the bridge foundation. The foundation is designed to remain stable even if an earthquake turns surrounding soil to liquid, which is a possibility in a large earthquake.

Red tape

Eighty percent of the money for the new bridge comes from the federal government. Tied to that funding are numerous government regulations.

For example, the Army Corps of Engineers requires that the shipping channels remain open at all times.

The project has employed stringent safety standards including elaborate platforms and safety railings. "Of course, this is time and money well spent if it saves lives," Hitt said.

One person died during construction of the old bridge. Another was struck by lightening but recovered.

Before the bridge could be built, expensive environmental studies were completed. And as the work is being done, all waste materials and other items must be kept out of the water.

"I'm sure back then concrete was dumped in the river and many other things were done that wouldn't be done today," Hitt said.

On Friday work was under way on the Missouri pier. The concrete structure is about 100 feet above the ground surface and will continue up about another 100 feet.

The next stage of the contract will be for the piers that go on land into Illinois. Bids should be let for this phase in February. The final phase will be to pour the bridge deck. If all goes as planned, the project will be finished by January 2001.