USAF – Repair North and West Areas Wells, Pump Station, Tower, and Transmission Mains

Coffman provided structural and corrosion control engineering services for the water distribution system upgrades for the north and west areas of Yokota Air Base, Japan. The scope included a 0.5 million-gallon elevated steel water storage tank (EST), two 3,500 sf pump houses, and three 250 sf well houses. The final deliverables included drawings, specifications, and the basis of design.

Structural engineering included steel and concrete structures, foundations, associated concrete equipment pads, and delegated design information. The location included design for both high wind and seismic loads. The preliminary design included research and coordination with the government and local contractors to determine the appropriate type and style of EST. The EST design consisted of a delegated steel superstructure and a concrete mat foundation on improved soils. The pump and well houses are concrete framed buildings.

Corrosion control engineering services included the design of an impressed current cathodic protection system for an elevated water storage tank constructed of welded steel. Design tasks included the development of design drawings and specifications for an internal system consisting of mixed metal oxide anodes, stationary reference electrodes, an automatic potential controlled rectifier, and associated cabling.