Bridge #15 over Tributary to Mud Creek

Bridge #15 Over Tributary to Mud Creek

S 3460 Rd in Pawnee County is an important road to citizens in this rural community, providing one of the few direct connections from SH-15 to an Arkansas River crossing. The old Bridge #15, a 40ft single span pony truss constructed in 1932, caused problems and inconvenience to those using this roadway: the unsafe and dilapidated bridge required frequent maintenance and repair and was thus often closed to traffic. When this happened, drivers, including emergency vehicles and school buses, were forced on a inconvenient detour.

GUY’s challenge in this complex project was to develop a bridge design that would fit the unique canyon-like shape of the channel. Our civil engineers determined that a standard PC beam would cost twice as much as usual because channel changes and large amounts of excavation would be required. In addition, this option would have a larger environmental impact. A concrete precast bridge was also not an option because the largest available option at the time  would not span the channel. A steel arch bridge was the only option that fit the needs of the project.

The new bridge is an innovative steel arch design that was ODOT’s largest structural plate bridge installation to date. This 64ft-2in span x 19ft-7in rise Steel Plate Structure was designed by GUY Engineering and constructed by Earth Smart Construction. With this arch design, GUY was able to minimize excavation costs in comparison to a standard PC beam bridge design. This bridge was the first ODOT-let project of this type of bridge in Oklahoma. 

The project also improved safety for drivers by including 1000ft of roadway to correct vertical sight distance deficiencies. The new bridge requires nearly zero maintenance – no joint maintenance, deck maintenance, beam corrosion, or any other maintenance items associated with traditional bridges. 

BR 15 Mud Creek before
Bridge #15 over Tributary to Mud Creek

Bridge #15 over Tributary to Mud Creek

Bridge and Approaches

JP 29924



Pawnee County

Expertise Provided:

Project management

Bridge and roadway design and geometrics

Hydrology and hydraulics


Utility relocation coordination

Right of way determination and documentation


Pawnee County, OK


 2019 ACEC Engineering Excellence Award