The aging Whiskey Creek culvert under OR 204 needed to be replaced according to the Oregon Department of Transportation (ODOT). The undersized structure was too deteriorated to justify repairs and caused challenges for the roadway, motorists and sensitive fish species.
Flooding was common during heavy rain or snow melt which created dangerous driving conditions and damaged the pavement and road structure. Less noticeable was the significant barrier the culvert created for salmon and steelhead. Depending on the water level, the fish couldn’t pass through the culvert and became stranded.
ODOT turned to Keller Associates for hydraulic engineering. We worked with ODOT staff to develop plans and specifications for the new culvert and oversaw construction. The final design included roughly 500 feet of stream channel enhancement and a new concrete box culvert to meet current design standards. Our staff also designed a fish ladder, sized the proposed culvert, sized the channel bed rock, and performed other hydraulics tasks and reports all while tying into the Grande Ronde River floodplain.
Design constraints meant the project required the hydraulic computation method of fish passage, a technical and demanding process with rigorous independent review from regulatory agencies. Further, with an archeological site on one side of the creek and sensitive wetlands on the other, project implementation brought many engineering challenges.
Critical to project success was the coordinated, proactive effort by Keller and ODOT to engage regulatory agencies early in the design process (pre-DAP) and keep them informed as the design progressed to facilitate buy in from all stakeholders.
This project was the recipient of the 2022 Environmental Excellence Award, as presented by the Federal Highway Administration to ODOT. Click here to find out more about the award.