The Hammond Bridge on Route CC spans the North Fork of the White River in Ozark County, Missouri, a premier destination for float trips and canoeing. The bridge serves tourists and is a critical connection for commuters and a school bus route. It is also the primary connection between the cities of Dora and West Plains.
When a 200-year storm washed the bridge away in May 2017, our team quickly designed a more durable replacement that could be constructed within 11 weeks and open in time for the start of the new school year. To encourage a faster turnaround, provided an incentive clause that rewarded the contractor for early completion. Our team provided final bridge plans just four weeks after the disaster.
Before work began, the project team began securing permits from state and federal agencies. The old bridge had washed several hundred feet downstream, and permission was needed from the U.S. Forest Service to put in a temporary access road for removal and to build at the current site. The project also required coordination with the U.S. Army Corps of Engineers to work within a navigable stream, the Missouri State Water Patrol to set up buoys around the old bridge to caution tourists, and the U.S. Fish and Wildlife Service to monitor protected species during removal of the old bridge.
The new, longer bridge has four spans that provide a larger waterway opening. For water to flow freely, the grade was raised by 1.5 feet and a four-girder line Nebraska University (NU) prestressed concrete arrangement provides more capacity at a shallower depth and accommodates larger loads. The new bridge shares the same two-lane roadway design element as the original, but it adds a 26-foot road bed lined with rustic guardrail and other structural adjustments to create a much sturdier structure.