Location: Snohomish County, WA
OCI was responsible for the Drainage Design and Temporary Sediment and Erosion Control (TESC) Design for the SR 9/92 Intersection Improvements Design Build Project in Snohomish County, WA. The main elements of the proposed development consist of widening SR 9 north of the intersection and widening SR 92 east of the intersection. A new signal system was added at the intersection to accommodate the widening. Improvements to the existing drainage system and stormwater quality were also addressed by constructing a detention pond, using natural dispersion facilities and Filterra systems for enhanced treatment and oil control. Specifically, OCI was in charge of the TESC Plans, TESC Narrative, Conveyance and BMP sizing, Water Quality Monitoring Plan, Drainage Plans, Hydraulic Report, Drainage Existing Conditions Survey, Downstream Analysis, and Special Provisions.