CABRILLO Historic Structures Report

COVER

Cover. Historic Photograph: The 60-inch Searchlight originally housed in Searchlight Shelter No. 5 (later numbered 18).

LIST OF FIGURES

EXECUTIVE SUMMARY

ADMINISTRATIVE DATA

INTRODUCTION

Purpose
Methodology

HISTORICAL DATA

History
Period of Significance

ARCHITECTURAL DATA

Army Radio Station
Electrical Connection Box
Searchlight Shelter No. 15
Searchlight Shelter No. 18
Searchlight Shelter No. 19
Generator Station for Searchlights No. 18 & No. 19
Base-End Station, Battery McGrath
Base-End Station, Batteries Calef & Wilkeson
Battery Commander Station, Batteries Calef & Wilkeson
Base-End Station at Billy Goat Point (Battery White Base-End Station)
Battery Commander and Base-End Station, Battery Humphreys
Base-End Stations, Batteries Woodward & Grant
Battery Commander and Base-End Station, Battery Ashburn
Battery Bluff, North Gun Emplacements
Battery Bluff, South Gun Emplacements
Battery Point Loma Panama Gun Mount
Battery Point Loma Bunker Complex, Guns 1 & 2
Battery Point Loma Bunker Complex, Guns 3 & 4
Battery Point Loma Reserve Magazine

MATERIAL DESCRIPTIONS, CONDITIONS AND REPAIRS

Approach
Repair Procedures
Concrete
Ferrous Metal
Wood Elements
Bituminous Roofing
Grade and Vegetation Issues
Paint
Graffiti

ULTIMATE TREATMENTS AND COST ESTIMATES

Army Radio Station
Electrical Connection Box
Searchlight Shelter No. 15
Searchlight Shelter No. 18
Searchlight Shelter No. 19
Generator Station for Searchlights No. 18 & No. 19
Base-End Station, Battery McGrath
Base-End Station, Batteries Calef & Wilkeson
Battery Commander Station, Batteries Calef & Wilkeson
Base-End Station at Billy Goat Point (Battery White Base-End Station)
Battery Commander and Base-End Station, Battery Humphreys
Base-End Stations, Batteries Woodward & Grant
Battery Commander and Base-End Station, Battery Ashburn
Battery Bluff, North Gun Emplacements
Battery Bluff, South Gun Emplacements
Battery Point Loma Panama Gun Mount
Battery Point Loma Bunker Complex, Guns 1 & 2
Battery Point Loma Bunker Complex, Guns 3 & 4
Battery Point Loma Reserve Magazine

APPENDIX I

Existing Conditions Drawings (omitted from the online edition)
Historic Drawings (omitted from the online edition)
Material Matrix
Bibliography
Glossary

APPENDIX II

Cost Estimate (detailed cost estimates omitted from the online edition)
Credits

Cover. Historic Photograph: The 60-inch Searchlight originally housed in Searchlight Shelter No. 5 (later numbered 18).

Figure 1. Historic Photograph: The 60-inch Searchlight No. 5 (later numbered 18) moves on narrow-gauge rail.

Figure 2. Historic Photograph: Battery Point Loma once featured 155 mm guns mounted on field carriages.

Figure 3. Map: Cabrillo National Monument Historic Harbor Defense Structures Locations.

Figure 4. Photograph: The Army Radio Station front façade.

Figure 5. Photograph: Roll-roofing clads the roof of the Army Radio Station.

Figure 6. Photograph: A non-original opening connects the Operating and Motor Generator Rooms.

Figure 7. Photograph: The small electrical box is located on the Bayside Trail.

Figure 8. Photograph: An overall view of Searchlight Shelter No. 15's structure visible above ground.

Figure 9. Photograph: Interior view of the elevator platform operating mechanism.

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

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

Figure 12. Photograph: Only the metal roofs and a concrete post are visible above ground.

Figure 13. Photograph: The underside of the elevator platform viewed from the pit.

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

Figure 15. Historic Photograph: The generator station prior to alteration.

Figure 16. Photograph: The missing metal observation slot shutters are located inside this structure.

Figure 17. Photograph: Unique to McGrath's base-end station, a storage compartment is present on the rear wall.

Figure 18. Photograph: Metal shutters in the open position allow visual access through observation slots.

Figure 19. Photograph: Embedded metal ladder rungs provide access from the hatch opening above.

Figure 20. Photograph: These structures are accessed through hatchways or observation slots.

Figure 21. Photograph: Electrical box debris and graffiti are the results of inactivity and vandalism.

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

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

Figure 24. Photograph: Rough-textured concrete provides camouflage for this structure.

Figure 25. Photograph: Embedded metal ladder rungs provide access to both floors of Ashburn's base-end station.

Figure 26. Photograph: This concrete gun emplacement is partially buried.

Figure 27. Photograph: Bolts to attach the weapon's base plate are visible at the north emplacement.

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

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

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

Figure 31. Photograph: Concrete cracks at Army Radio Station headers.

Figure 32. Photograph: Concrete cracks at base of Battery Calef & Wilkeson Base-end Station hatch.

Figure 33. Photograph: Spalled concrete post at Searchlight Shelter No. 15.

Figure 34. Photograph: Missing corner and exposed reinforcing rod at lower Billy Goat Point Base-End Station.

Figure 35. Photograph: Exposed reinforcing rod and spalls at Calef & Wilkeson.

Figure 36. Photograph: Coating failure and corrosion at Searchlight Shelter No. 15.

Figure 37. Photograph: Metal corrosion of hatch at the Battery Commander Station, Battery Humphreys.

Figure 38. Photograph: Missing roof vent and metal corrosion at Searchlight Shelter No. 15

Figure 39. Photograph: Deteriorated wood curb at Searchlight Shelter No. 15.

Figure 40. Photograph: Transit graffiti at the Base-End Station, Batteries Calef & Wilkeson.

Figure 41. Photograph: Transit graffiti at the Battery Commander Station, Battery Humphreys.

Figure 42. Photograph: Graffiti on corrugated metal at Battery Point Loma Bunker Complex.