CABRILLO Historic Structures Report

Figure 29. Small corrugated metal structures served the four Panama Mounts once here.

BATTERY POINT LOMA BUNKER COMPLEX, GUNS 1 & 2 (Stabilization)
BATTERY POINT LOMA BUNKER COMPLEX, GUNS 3 & 4 (Stabilization)
BATTERY POINT LOMA RESERVE MAGAZINE

Location

These structures are located on the west side of Point Loma, originally supporting the four Panama gun mounts located nearby.

History

These bunker complexes each consist of five structures; one located to the south of each gun, one to the north of each gun and one to the east situated between the guns. Associated with the Panama Mounts, these corrugated metal bunkers connected to a communications tunnel at the rear of the battery. Actively used from 1941-42, they were abandoned in 1943. The bunkers were either ready magazines, storage facilities or sleeping quarters. The reserve magazine might be the magazine specified in 1936 drawings, with a later conversion into a bunkroom.

Description

Exterior

Partially covered with earth and vegetation, these quarter-inch thick corrugated metal barrel vault structures range from seven-and-one half to ten-feet long, and are ten-feet wide (figure 29). Exposed corrugated metal, approximately four foot wide panels bolted together, form both the ceilings and the walls of these structures. The panels run the length of the bunkers. Corrugations are six-and-one-half inches on center and about one-and-a-half inches deep. The metal panels are connected with two-inch threaded bolts with square nuts, the joints overlapping about five-inches. Some of these bunkers are almost entirely buried and the interiors of others are relatively free of debris.

The reserve magazine (storeroom/sleeping quarters) is a partially buried, corrugated metal barrel vault covered with a 12-inch layer of concrete (figure 30). Ten-feet wide and forty-feet long, only the ends of the structure are visible, the remainder covered by earth and vegetation, creating an artificial hill.

Interior

One of the bunkers has an intact wooden rear wall constructed of five-inch wide boards with two-inch wide cross pieces. Two collapsed corrugated pipes are inside.

At the reserve magazine, the remains of wood one-by-three inch tongue-and-groove flooring and a built-in wood and chicken wire bunk or storage assembly are scattered about the floor with other debris.

Condition

The corrugated metal bunkers range from partially infilled to almost entirely infilled with earth and vegetation from the site. Their condition is difficult to access. The exterior exposed portions of the metal structures are heavily corroded and the interiors viewed showed signs of galvanization.

Reserve Magazine: the concrete curbs at the base of the walls, which apparently once supported the wooden infrastructure, have collapsed, taking the wooden elements with them. The structures are overgrown with vegetation.

Structural Analysis

No major structural concerns were noted. The wood retaining wall at the north end of the south bunker at Guns 3 and 4 is decaying and does not appear to be well tied to the steel pipe. Several bolts or nuts that tie together the sections of the steel pipe at the reserve magazine structure are missing, however this is not serious. Sections of the concrete support for the wood bed frames have collapsed, however this does not affect the overall stability of the structure.

Figure 30. Collapsed wood and chicken wire assemblies are visible at the entrance.