CABRILLO Historic Structures Report

Figure 10. Originally 75-feet of narrow-gauge rail extended out, but only five feet remain today.

SEARCHLIGHT SHELTER NO. 18 (Restoration)

Location

This structure is located on the Bayside Trail, near Searchlight Shelter No. 19 and the Generator Station for Searchlight No. 18 and No. 19.

History

Constructed in 1918-1919, this World War I structure sheltered a 60-inch searchlight mounted on narrow-gauge rails. The approximately 75 feet of rails extended from the structure up the Bayside Trail, allowing the searchlight movement to a point overlooking the harbor entry. Originally named Searchlight No. 5, the searchlight shelter was renamed No. 11 in 1936 when additional searchlights were added to the coastal defense system. The searchlight was renamed No. 18 during WWII. This structure currently contains a searchlight, which is not the original. The searchlight is not mounted on the tracks inside the shelter. The shelter remains closed to the public.

Description

Exterior

This single-story reinforced concrete structure is rectangular in plan. Its flat, vegetation-camouflaged roof features a drip edge at the front, and a twelve inch diameter clay ventilation pipe penetrating the roof toward the rear of the structure. Thirteen foot high double access doors are wood-framed, clad in metal, and painted drab green (figure 10). The remains of the narrow gauge rails protrude from underneath these doors, terminating approximately five feet in front of the structure.

Interior

The single, rectangular room features a concrete slab floor, and concrete walls and ceiling with visible formwork lines. A cable pit near the doors provided electrical service from the nearby generator station. Removable two-by-four wood boards cover the cable pit, currently filled with water. Iron narrow-gauge rails, visible from the exterior, are embedded in the concrete floor, stopping halfway into the interior (figure 11).

Condition

Exterior and interior

The building is in good condition. Deterioration includes erosion of the surrounding hillside, minor corrosion at the doors, and damage to the clay vent pipe.

Structural Analysis

No significant structural concerns were noted. The concrete is in good condition with only very minor cracking.

Figure 11. The 60-inch Searchlight originally housed in Searchlight Shelter No. 5 (later numbered 18).