CABRILLO Historic Structures Report

Figure 28. An overall view of the Panama Mount looking west toward the Pacific Ocean.

BATTERY POINT LOMA PANAMA GUN MOUNT (Stabilization)

Location

This structure is located on the west side of Point Loma. Nearby structures associated with these mounts include the bunker complexes and the storeroom/sleeping quarters.

History

In 1939, four 155 mm guns were brought to Fort Rosecrans. Emplacements for the guns were begun on the west side of Point Loma in 1941 when funds became available. The mounts were completed in January of 1942. The guns were emplaced on Panama mounts with a traverse of 360 degrees, located 90 feet apart from center-to-center. An underground communications trench connected the four guns. The guns were actively used during 1941-42, staffed by Battery E of the 19th Coast Artillery. This battery served as the examination or "challenge" battery for ships approaching the water areas to the west and northwest of San Diego Harbor. Following Pearl Harbor, they served as the primary anti-submarine battery. The guns were abandoned in 1943 with the completion of the 90mm AMTB Battery Cabrillo installation. Although three of the mounts are no longer visible, archaeologists uncovered the mount of gun number four during the mid-1980s.

Description

This emplacement consists of two concrete rings. An inner, ten feet in diameter circular concrete base banded with iron located at the center of the emplacement seated the gun. The outer ring is three feet wide and 38 feet six inches in diameter. The guns' trails rested and turned on the steel rails embedded in this outer ring. One of the rails is smooth, the other is toothed. The emplacement is approximately three feet high, although only about 12-inches remains visible (figure 28).

Condition

The only visible mount, number four, was stabilized when it was excavated during the mid-1980s. Stabilization included the treatment and painting of metal elements.

The central concrete portion of the mount exhibits cracking at the beveled edge and across the top surface. The steel band encircling this element is delaminated and the bolts are missing. The outer concrete ring is partially covered at the northeast side due to slope erosion. Some concrete erosion and spalling is present. All metal components show signs of corrosion and are in need of paint.

Structural Analysis

No significant structural concerns were noted. The cracking and spalls in the concrete ring structures are relatively minor and do not at this time appear to compromise the structure's capacity.