Residual Overland Flow

Cornerstone Structural Engineering Group provided engineering services for the design of new cast-in-place headwalls for a precast concrete box culvert and multiple cast-in-place concrete retaining walls in the City of Napa. The new structures are part of the Residual Overland Flow project which is intended to provide drainage improvements in the vicinity of the site from residual flows from Tulocay Creek, a tributary to the Napa River, during a rare storm event. The box culvert and retaining walls were proposed to provide access to a new development by the Gasser Foundation, just north of Soscol Avenue and between the proposed Gasser Drive Extension and Oil Company Road.  The culvert and retaining walls included architectural elements such as pilasters, electroliers, and architectural treatment on the headwalls of the culvert and face of retaining walls. The project finished construction in 2018.