CABRILLO Historic Structures Report

Figure 14. Nestled in the hill, this generator station served Searchlights No. 18 and No. 19.

GENERATOR STATION FOR SEARCHLIGHT NO. 18 & NO. 19 (Restoration)

Location

This structure is situated in a ravine along the Bayside Trail and supplied power to Searchlight No. 18 and No. 19.

History

Constructed in 1918-1919 to serve Searchlights No. 5 and No. 6 (later renamed No. 18 and No. 19), this World War I structure is one of three known stations of its type. When operational, the structure contained two Fairbanks-Morse gasoline-powered 25kw generators. These generators featured four cylinder engines, 560 RPM, 43/54 horsepower and delivered direct current power to the searchlights. Two underground gasoline tanks located in front of the station were removed in 1985. The station remains closed to the public.

Description

Exterior

This single-story flat-roofed reinforced concrete structure is rectangular in plan. The primary facade features two riveted metal doors with windows above, one large window and a plywood-infilled doorway (figure 14). The three windows feature projecting concrete sills and vertical steel security bars. One exhaust vent protrudes from this wall and the hole remains from another, although the vent is gone. Two vents also penetrate the roof. Alterations include the widening of the larger door, originally a single wood door leading into the engine room; and the infill of a second large window (figure 15). The two smaller windows located above the metals doors, originally glazed, are covered with chicken wire. The remaining larger window, also originally glazed, is now sealed with plywood.

Interior

The two rectangular interior rooms feature concrete slab flooring, and reinforced walls and ceilings. A four-inch wide flat wood surround, partially missing, trims the opening connecting the radiator and the engine rooms. Alterations to the engine room include removal of the generating sets and the widening of the exterior doorway, requiring infill of an original window opening.

Condition

Exterior

Concrete is in good condition with select spalling occurring at the drip edge and at ferrous metal attachments (hinges and vents). Paint has peeled away, especially where vegetation once covered the side facade.

Interior

Corroded reinforcing rod has caused concrete spalling at the metal door header. Numerous impact spalls speckle the walls and ceiling.

Structural Analysis

No significant structural concerns were noted. The minor cracking and spalling in the concrete walls do not at this time compromise the structural capacity of the building. The corroded reinforcing rod at the pockets above the door headers appears to have been left exposed during the original construction. The spalls on the interior walls appear to be the result of impact rather than concrete deterioration.

Figure 15. The generator station prior to alteration.