Anderson, Alvin G.Anderson, David J.2011-08-312011-08-311968-02https://hdl.handle.net/11299/114209The Foothill Feeder Project of the Metropolitan Water District of Southern California incorporates a long tunnel that will be part of the system which will supply water to a large area in Southern California. In this system head control devices are needed to regulate the discharge through the tunnels and the appurtenant structures, and for this purpose gated structures open to the atmosphere were chosen. The gate structures, circular in plan with the necessary emergency overflow weirs, were made large enough so that machinery access into the tunnel for maintenance could be incorporated in the structure. The circular plan also provided certain structural advantages. The research described in this report was carried out to study in detail the hydraulic characteristics for a wide variety of flow conditions for one of these structures, the Big Tujunga Gate and Spillway Structure.en-USReport