Leaders of the US House Transportation and Infrastructure Committee have asked federal inspectors to expand their investigation into the safety of a US$ 600 million transportation project in Nevada following the discovery of cracks in the under construction Galena Creek bridge.
In a letter to the investigative team, leaders of the Committee said, "Given the recent developments, we are requesting that you expand the scope of this investigation to include the deficiencies discovered on the Galena Creek bridge."
At 300 ft (91.5 m) high and 1700 ft (518 m) long, with a supporting cathedral arch, the Galena Creek bridge will be the largest structure of its type in the world.
It is estimated it would cost US$ 1 million to repair the cracks in the concrete supports of the arch that are up to 30 ft (9.2 m) long and about ½" (12 mm) wide.
The move follows a US Department of Transportation's (DoT) Office of Inspector General investigation, launched in January, into construction of the smaller the Galena Forest bridge after ex-construction worker David Lee complained he'd been ordered to do substandard concrete work to save money.
The Nevada Department of Transportation (NDOT) claims the cracks are not indicative of major structural problems. However, the Committee's letter said, "some believe the design deficiency could shorten the bridge's life-span by up to 10 years."
An NDOT spokesman said it welcomed further investigation and the safety of Galena Creek bridge has not been compromised and construction should be completed late next year.
The four affected areas of the Galena Creek bridge's southbound span will be strengthened with reinforcing steel and concrete, and cracks will be filled with epoxy at a cost of up to US$ 900000, said an NDOT spokesman.
In a statement the NDOT said the state would pay for the repairs because the bridge, one of nine on the project, was designed by its own engineers.
The Galena Creek bridge is part of the I-580 Freeway Extension Project currently under construction between the Mt. Rose Highway in Galenaand the Bowers Mansion cutoff in Washoe Valley.
The new section will be an 8.5 mile (13.7 km) highway and when completed in 2011 will provide a limited access freeway link from Reno to Carson City.
The design of the Galena Creek Bridge a cathedral arch and. according to the NDOT, it will be the largest such structure in the world at 1700 ft (518 m) long, with an arch span of 690 ft (210 m), when finished.
Twin arches will support a bridge deck nearly 300 ft (91.5 m) above the creek.