CABRILLO Historic Structures Report

Figure 22. Battery commander station and base-end station, Battery Humphreys. Rough-textured concrete roofs provide camouflage for these structures.

BATTERY COMMANDER STATION AND BASE-END STATION, BATTERY HUMPHREYS (Restoration)
BASE-END STATIONS, BATTERIES WOODWARD & GRANT (Restoration)

Location

Both structures are located on the west side of Point Loma, directly below the whale overlook. The upper structure is the Battery Commander Station and Base-End Station, Battery Humphreys. The lower structure is the Base-End Stations, Batteries Woodward and Grant.

History

This pair of structures was constructed c.1936-1941, for use during World War II. The upper level of the upper structure served as the battery commander's station for Battery Humphreys, which had two six-inch guns, while the lower level served as the base-end station. The upper level of the lower structure served as the base-end station for Battery Woodward, which was located at the north end of Fort Rosecrans, and the lower level served as the base-end station for Battery Grant at Fort Emory. The structures are currently vacant and are not open to the public.

Description

Exterior

These multi-level, partially underground structures are configured roughly by their two mounded semi-circular concrete roofs (figure 22). Rough aggregate concrete with embedded steel rings cover the roofs. The steel rings were used to anchor camouflage covering. Square ferrous metal roof hatches access the interiors. The concrete walls at both levels feature observation slots facing the Pacific, protected by eight solid metal, green-painted, rectangular shutters. Hardware allows the shutters to be fixed open or closed. Miscellaneous PVC pipes are visible, formerly supplying either water or electricity.

Interior

These two-story structures each contain three rooms, one at the upper level and two at the lower. All three rooms are rectangular in plan with concrete floors, walls and ceilings. Access to the structures is through roof-mounted manholes, down steel rungs embedded into the upper-rooms' northern walls. The lower level rooms are accessed from the upper again via manhole and wall-embedded steel rungs. The upper level rooms feature one-inch galvanized pipe railing, plywood shelving, miscellaneous conduit, a telephone box and the remains of a concrete azimuth instrument stand. The rear lower room contains a cable pit in the northeast corner, a metal azimuth instrument stand on the ground, miscellaneous conduit and a fuse box. The forward lower level room was the base-end station used for observation, located two steps up. The room contains an octagonal concrete depression position finder base, a metal azimuth instrument stand and miscellaneous conduit (figure 23).

Condition

Battery Commander Station and Base-End Station, Battery Humphreys

Exterior

Concrete wall deterioration includes minor erosion, spalls, cracks and exposed reinforcing rod ends. Minor cracks and spalls are present at the east end of the structure and a portion of the lower-level roof is missing. A rust hole and overall minor corrosion mars the entry hatch. Corrosion is also present on the shutter hinges.

Interior

Conditions in the upper level room include: a hairline crack along the south wall; missing wall attachments at the north and south walls; peeling paint at the ceiling; a raised, rough spot on the floor where the azimuth instrument stand was removed; debris; and spalling around the three-inch pipe on the east elevation. The azimuth instrument stand, missing from the lower level front room, lays on its side in the lower level rear room. Overall the interior is in good condition.

Base-End Stations, Batteries Woodward and Grant

Exterior

Concrete deterioration includes minor spalls and exposed rebar, especially on the upper portion of the west wall. Some stones are missing from the roof camouflage and others have separated from the roof concrete creating gaps. The access hatch has several rust holes and overall corrosion. One of the hatch cover hinges is severed. Vegetation is encroaching from the rear of the structure.

Interior

The upper level room contains debris, graffiti on the concrete wall surfaces, and minor corrosion on the metal shutters. The lower level front room exhibits minor efflorescence, especially at the wall base, and minor spalling at ferrous metal wall attachments. Corrosion is present on the metal ladder rungs in the lower level rear room, but the rungs are still sound.

Structural Analysis

No significant structural concerns were noted. The cracks and spalling in the concrete walls and roof noted above are relatively minor and do not at this time appear to compromise the structure's capacity.

Figure 23. A depression position finder with extant swivel bench, typical to both structures.