Project Details

Hydrologic and Hydraulic analysis of highway structures requires Banner's engineers to identify the size and characteristics of drainage basins that contribute flow to culverts, box culverts, or bridges at highway crossings, to determine the basin hydrology. Banner uses both on site hand survey as well as LiDAR aerial survey technology to identify break lines in topography and other features that determine the direction and rate of flow. Engineers then utilize the survey and basin hydrology to analyze the hydraulic performance of the existing highway structure and propose replacement options that consider many factors such as constructability, cost, impacts to flood plains, and impacts to environmentally sensitive sites. The analysis is performed by creating a 2-dimensional hydraulic model using SMS SRH 2D modeling software, which creates a realistic terrain model and crossing features to closely resemble the structure performance during various rain events. Structure replacement options are discussed on site with the Owner and a Hydraulic Design Report and Hydraulic Data Sheet are provided to detail the existing crossing analysis and the justification for the proposed replacement structure.

In Brookings County, we helped secure funding through the Bridge Improvement Grant (BIG) for evaluating their structure. Our team used cutting edge LiDAR-equipped drones to gather detailed data on the existing structures and project sites. During the design phase, engineers analyzed this data to create design options, accounting for constructability, cost, and impacts to floodplains and the environment overall. The project engineers modeled various rain and flood events to test the performance of the designs alongside other factors. The team also prepared reports and met with stakeholders, helping everyone make informed decisions throughout the project.