In December of 2018, West Yost conducted a site visit at the damaged Drainage 2 outfall. We documented the condition of the outfall and the surrounding area in photographs and prepared a PowerPoint that included all the photographs along with captions describing the photo’s location. West Yost coordinated with Dokken Engineering (Dokken) regarding permitting issues on repairing the damaged culvert. West Yost researched flows in the American River during the storm that preceded the bank failure and included that information in the PowerPoint sent to the City.
West Yost evaluated several alternatives to repair the Drainage 2 pipe outfall. The alternatives were for different pipe and river bank configurations and may include alternatives such as relocating the outfall, replacing the outfall in the existing location and sloping back the existing vertical river bank, replacing the outfall in the existing location and rebuilding the river bank to its previous location.
We also evaluate different techniques to armor the river bank to protect the repaired outfall. For each alternative, West Yost will prepared a cost estimate and a figure illustrating the design concept.
West Yost met with the City to review the figures and cost information. West Yost modified the conceptual design previously provided the conceptual design was the basis for permitting and construction of the damaged Drainage 2 outfall.