Location: Salt River Project Main Campus
Survey Number: HPS-183
Year Built: 1914
Architectural Style: Neo Classical
The 1914 Neo-Classical style Salt River Project Cross Cut Power Plant is significant as the only hydroelectric structure remaining in the Salt River Valley and for its association with the historic electrification of the valley following construction of Roosevelt Dam.
A: HISTORIC EVENTS
Built by the Bureau of Reclamation in 1914, initial construction was followed in 1938 with subsequent work. The Cross Cut Power Plant the largest low-head hydroelectric plant in the SRP system. From about 1915 to 1938, it represented a large percentage of the SRP generating capacity. The main use of electricity originally was to run water pumps, especially on the Western Canal. Two seven-foot penstocks took water from the Arizona Cross Cut Canal, and dropped it 112 feet through the Pelton water wheels, which turned Westinghouse generators, generating 11,000 volts. The plant eventually serviced some of Tempe, including the Hayden Flour Mill when it was converted from hydropower to electric power in the 1920s.
The Power Plant is a rectangular (176 ft. by 42 ft.) cast-in-place concrete structure with a gable roof and ridge vents. The rectangular mass is divided into 12 bays (north to south) along the sides and three bays on the sides. The maximum height of the structure is 63 ft. with the main generator floor 22 feet above the tailrace (water exit) grade. The concrete work is detailed with simplified classical motifs, expressed below the frieze panels by a corbelled band course and pilaster capitols. The roof is supported by metal trusses. The windows (one per bay) are metal 4-over-4 light double-hung. The plant is entered from the north with a garage door access from the south. To the east is the switching and transformer building (which measures 89 ft. by 43 ft.) and a shop (16 ft. by 43 ft.). These buildings are of concrete with similar detailing and openings, but with a flat concrete roof. Some of the original equipment remains in the plant, but it is not used at this time. In 1938 a metal steam generating plant powered by diesel engines was constructed to the northwest. This large Moderne-like building is sheathed in corrugated metal with multi-pane steel-frame awning windows. This plant remains on stand by.
Tempe History Museum Historic Property Survey: HPS-183
Historic American Engineering Record: HAER AZ-30 Cross Cut Hydro Plant, Tempe