About 60 freight trains are running daily across the new bridge, which went into service Aug. 20 about three miles west of Boone, Davis said. The structure's opening has also marked the end of service for the nearby historic Kate Shelley Bridge. The Kate Shelley Bridge, more than a century old, dates to the era of steam engines puffing smoke as they chugged through Iowa. The aging bridge, which is just south of the new bridge, is about 185 feet tall. The old structure will remain because it is a historic landmark, although it won't handle train service, Davis said.
The Kate Shelley Bridge has been a tourist attraction for decades, and the new bridge will be, too, said Fenner Stevenson, general manager of the Boone & Scenic Valley Railway, a tourist railroad. His trains operate on their own tracks and do not use the Kate Shelley Bridge.
"People who love railroad bridges can see two of the tallest bridges in the world right here," Stevenson said. "Countless numbers of people come to Boone to ride our train and then they say, ‘How do we get to the Kate Shelley High Bridge?' "
The Kate Shelley Bridge has long been a marvel for railroad historians because of its impressive height and design and also because of the story surrounding the bridge's namesake. In 1881, Kate Shelley, 15, made her way by lantern through a ferocious storm to warn a railroad agent that the storm had washed out a railroad trestle south of Boone, wrecking a train. Because of her effort, the agent was able to halt an oncoming passenger train.
The Union Pacific's new concrete and steel structure can accommodate two freight trains operating at speeds up to 70 mph. The old bridge could only serve one train at a time, with a speed of about 25 mph. The new structure will eliminate a bottleneck for trains traveling a major corridor between the West Coast and Chicago, said Craig O'Riley, a planner for the Iowa Department of Transportation.
The Union Pacific's main line across Iowa carries coal from Wyoming's Powder River Basin, as well as freight containers from the West Coast that began their journeys on ships at Asian ports. The trains also haul grain and mixed freight.
"The new bridge makes a lot of sense," O'Riley said. "Think of driving across the Des Moines River in your car and saying, 'I can't be on the bridge with any other cars.' It's a big issue."
The contractor for the new bridge's construction was OCCI Inc. of Fulton, Mo. The engineering was handled by HDR Engineering Inc. of Omaha. Work on the bridge began in late 2006 with the goal of finishing in November 2008. But construction ran late.
"The project was a challenge with its height and design," Davis said.
A formal ribbon-cutting for the new bridge is planned Oct. 1. The bridge construction has been closely watched in Boone, which has a long history of involvement with the railroad industry. Many of Boone's 12,803 residents have worked for the Union Pacific or the former Chicago & North Western Railway, or are involved with the Boone & Scenic Valley Railroad. Former Boone mayor George Maybee, a former railroad division manager, said he's impressed with the towering new railroad structure. He toured the bridge while it was being built, and he's watched freight trains on it.
"It's beautiful, and when you see the two of the bridges together, it's really something," he said.