Cottonwood Road Drainage Study

Aspect provided drainage analysis and planning services to the City of Walla Walla for an area of proposed residential development with a history of drainage, flooding, water quality, and ditch/culvert maintenance problems. The goal of the project was to develop an integrated regional alternative to reduce flooding hazards and sediment loading along the Cottonwood Road area. We assessed existing drainage infrastructure, completed a hydrologic and hydraulic analysis of the project area, and developed alternatives to reduce sediment and flooding hazards, including ditch treatment techniques, a sedimentation pond, and regional stormwater conveyance improvements.