A routine inspection revealed that a bridge support on the south side of Deep Creek had been eroded and a scour hole was created, which destabilized the base of the support.
Cardno worked with Clackamas County to provide design plans to stabilize the bridge support and embankament, as well as restore the stream flow. The design protected the bridge abutment against scouring forces and realigned the main creek channel.
As part of the stream restoration, Cardno evaluated the natural processes within the project, including:
- Channel migration history and potential areas of future migration
- Qualitative sediment transport
- Grain size distribution
- The impact of the north abutment fill and riparian conditions
- The role of large woody debris in controlling channel processes
Cardno provided the plans, specifications, and engineer’s estimate for Clackamas County to solicit bids from local contractors.