Our team provided bridge inspection on the 156-foot-long Amisigger Road Bridge and several hundred feet along Deep Creek both upstream and downstream of the bridge.
A routine bridge inspection revealed a bridge support on the south side of Deep Creek had been eroded and a scour hole was created, which destabilized the support base.
Cardno worked with Clackamas County to provide design plans to stabilize the bridge support and embankment along with habitat restoration.
The design protected the bridge abutment against scouring forces and realigned the main creek channel.
In addition, Cardno evaluated the natural processes within the project reach, 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, and
- the role of large woody debris in controlling channel processes
Cardno also provided the plans, specifications, and engineers’ estimate for Clackamas County to solicit bids from local contractors.