Amelia Earhart Memorial Bridge Replacement

Atchison, Kansas, and Winthrop, Missouri

Network tied-arch design delivers safety, mobility


•    First network tied arch adds safety, reduces cost
•    Span doubles traffic capacity
•    Bridge features innovative floor system and easier maintenance

HNTB designed the 2,500-foot Amelia Earhart Memorial Bridge and approach, a joint project of the Kansas and Missouri departments of transportation.

HNTB’s design:
•    Employs a network tied-arch technique to add safety and redundancy while reducing cost compared to a traditional tied arch. 
•    Features a 527-foot span — longer than required for the navigation channel — to mitigate a scour problem caused by swirling current and to add stability. 
•    Reduced the superstructure depth. A street intersection on one approach required the bridge to have a fixed grade. The solution was an innovative floor system that framed the stringers into the floor beams, so the tops of the floor beams and stringers align.

The span accommodates four 12-foot lanes and two 10-foot shoulders with aesthetic lights. Access openings and a below-deck catwalk aid in maintenance and help ensure long-term safety. 

The new bridge handles twice the capacity of the former crossing.