Teton Creek Bridge Replacement & Stream Restoration
Teton County, Idaho, ID, USA
Teton County Idaho Public Works Department
An intensive stream, riparian, and bridge restoration project along almost one mile of Teton Creek.
Services
Landscape Design
Civil Engineering
Hydraulic Analysis
Permitting
About the project
This project was an intensive stream, riparian, and bridge restoration project along almost 1 mile of Teton Creek. The final restoration design balances flood hazard mitigation, protection of existing infrastructure development, and riparian and stream ecological function. Harmony provided HEC-RAS modeling of Teton Creek which was used as the basis for the restoration design and channel modifications. HEC-RAS version 4.0 was used and the reach includes one split flow and two bridges. As a consultant to Teton County, Harmony provided preliminary bridge plans which included horizontal and vertical layout, scour analysis, footing design and wingwall design. The Teton Creek Bridge replacement was an important first step to the restoration project which was completed in 2014. The new bridge allows for conveyance of the 1% annual chance (100-year) flows in Teton Creek and 2-ft of freeboard above the 2% annual chance (50-year) peak flows.
How we did it
These projects included the replacement of two bridges along Badger Creek, and a bridge on Darby Creek at S2000E, as well as related stream bank stabilization, riparian restoration, and ecological functionality. Harmony Design & Engineering lead the design team that worked together seamlessly to provide surveying, hydraulic analysis, hydrologic analysis, morphologic review, structural engineering, and final construction documents for the three bridges and associated stream channel modifications. This team also provided permitting assistance to Teton County, ID. Harmony completed the hydraulic analysis, hydraulic structure selection and design, and road reconstruction design. Bridge designs balance cost with hydraulic effectiveness while road re-construction design was guided by County design standards for stopping sight distance in order to improve safety. These efforts restored proper fluvial process, protected public infrastructure and safety, and addressed flood conditions that have destroyed Teton County roadways numerous times in the recent past.
