Large Diameter Water Transmission Mains
City of Fresno, California

West Yost has completed preliminary design and is completing final design of two major water transmission mains for the City.  An alignment study for the two transmission mains (24- and 36-inch diameter pipes) was required to minimize community and environmental impacts, and assure a cost effective, constructible project. The alignment study included detailed analysis for numerous crossings and evaluation of construction methods. Potential crossings include: Highway 99, Highway 168, Fresno Street, the railroad, and two irrigation canals.

One of the new pipelines, the Chestnut Avenue Alignment, is a 36/30-inch diameter pipeline that passes through four pressure zones and will require pressure reducing stations to drop the pressure in the three lower pressure zones. The pressure-reducing stations will be controlled through connections with the City’s SCADA network.

The second pipeline, the Downtown Alignment, is a 16/24-inch diameter pipeline to provide water to downtown Fresno from two wells northeast of the downtown area. Each pipeline required an alignment study to minimize community and environmental impacts, and assure a cost-effective, constructible project. Numerous trenchless crossings are required including railroad tracks, irrigation canals, and two state highways.