FIELD NOTES:
PLACE:	CORREGIDOR	DATE:	24 DEC 2012
LOCALITY:	MALINTA HILL
SUBJECT:	THE MALINTA TUNNEL, FROM CONCEPT TO COMPLETION
BY:	JOHN MOFFITT
	REF: FOTS2/121224

 

Along with the big guns, one thing that continually draws me to Corregidor Island is the “Malinta Storage System” (commonly referred to as “Malinta Tunnel”). I have no idea why it fascinates me but I have spent hours wandering around the complex. No doubt part of the attraction is the ‘unknowns’ that even after collecting all this information still remain. The following Trip Report will give you (1) history of the tunnel, (2) pre/post war photos and (3) a good look at what you will see there today. Due to the volume of material, I will split the report into these three sections.

In the past while searching for Malinta Tunnel information I rarely found more than a couple paragraphs and most of that was incorrect. I thought it was time to piece the scraps together for anyone else on these forums who may be interested.

While trying to research this subject, I encountered the usual cases of disagreeing information so what I present here is a summary based on what I understand to be correct. I consider the most reliable information to come from the US Army’s ‘Corps of Engineers’. This includes correspondence, official blueprints and Records of Completed Works. These are factual records recorded by Army Engineers as the work progressed. Various books were a secondary source. There may be errors and I would appreciate being corrected if anyone can produce differing evidence.

By far the biggest (and widely accepted) misconception is the tunnel construction dates. Numerous internet searches plus books and articles state that the Malinta Tunnel was built during the ten year period between 1922 and 1932. These dates are also quoted daily to tourists who visit the island. I can see where this idea may have come from though. One of the tunnel entrances has these dates stenciled on it.

1966 Photo of the Malinta Tunnel North entrance

Bilibid Stockade

Bilibid Stockade

Wouldn’t it be great if we could speak to the man in charge of constructing Malinta tunnel to get the real story? What could be better than that? Well, we don’t need to, he wrote an account of his Corregidor experience and it is available on Corregidor.org. This officer, Lt. Paschal N. Strong of the US Army Corps of Engineers, arrived in the Philippines in 1932 and was promptly put to work.

http://corregidor.org/chs_lean_years/leanyear_01.htm

For the 831.6 ft. long main shaft, work commenced simultaneously from both the east and west entrances. This dome shaped shaft had a minimum size of 18 ft. high and 24 ft. wide. Initially the tunnel was unlined. It would also accommodate dual trolley lines. When the two work crews met, the shaft sections lined up within inches of each other. The year was 1932 which was recorded above both tunnel entrances.

The Malinta Tunnel (West entrance) during construction.

A trolley car at the west entrance.

The Malinta Tunnel east entrance in 1945

The blasting of 24 north and south side laterals was already underway. (22 were for storage facilities as mentioned above and two were passageways to the North and South Systems). Connecting the rear of all laterals was a 4 ft. x 6 ft. ventilation shaft. One air vent from the south side ventilation shaft up to the surface was also constructed.

Soon large chunks of flaky rock began falling from the ceiling throughout this unlined tunnel. The new Harbour Commander, Brig. Gen. S D Embick, decided in April of 1933 to line the main shaft and laterals with concrete. He was able to acquire sufficient funds so his staff went shopping. The source that quoted the lowest price including shipping to the Philippines was Japan. On June 30, 1934, the Corps of Engineers issued a Report of Completed Works (RCW) reporting that the central system including the main shaft and adjacent laterals were complete.

RCW for the Malinta Central System.

Meanwhile work was also progressing on the North and South Systems. As of June 30, 1934, the status of the North System was as follows: the main 531 ft. long north-south shaft had been excavated from the Malinta central tunnel to the North Shore Road. Roughly half its length was still a pilot tunnel but the rest was full size. Of the 12 laterals, 10 were partially dug pilot tunnels and the final 2 had yet to be started. Additional work to be completed involved 2 ventilation shafts at the rear of all laterals and 2 exterior ventilation shafts out to the hillside. Everything except the 2 rear 4 ft. x 6 ft. ventilation shafts would be concrete lined. It would be another three years before the North System was reported as complete on May 26, 1937.
 

RCW for the Malinta North System

Blueprint for the Malinta North System.

The South System was to be a much larger complex with a central shaft in excess of 600 feet in length. Storage would be provided by 32 laterals (each 112 ft. long) and there would be an exit out to the SW corner of Malinta Hill. This system was for Quartermaster Corps materials. The status of this system on June 30, 1934 was as follows: a pilot tunnel from the south entrance to 410 ft. along the central shaft had been blasted. Of the 32 laterals, 4 at the south end of the complex were partially completed pilot tunnels; the rest had not yet been started. At the north end of this complex where it joined to the Malinta Central System (at the 3rd lateral from the SW corner), only a few feet of tunnel had been blasted.

I cannot determine the exact date but shortly after June of 1934, there was a massive cave-in along the central shaft of this system starting just before Lateral #1 and ending at Lateral #16. The part of Malinta Hill where this system was being constructed had been found to have softer rock than other areas. A decision was made to abandon all work to date (except the south entrance) in favor of relocating the South System further east into more solid rock. The connecting point between the South System and the Malinta Central System would now be at Lateral #8 of the main complex.

Slight design changes were implemented in that there would now be 33 laterals. The requirement for a tunnel entrance would still be met by utilizing the existing south entrance already built at the previous South System location. To accomplish this, a new tunnel to connect the SW entrance to the relocated South System was added.

Work must have progressed quickly as by June 30, 1935, a pilot tunnel over 500 feet long existed from the Malinta Central System (Lateral #8) down to the southern end of the QMC tunnels. From there another pilot tunnel continued west for another 279.4 feet where it intersected the SW tunnel entrance. Also, work on the 4 most northern laterals had been started.

The next area of the Malinta Tunnel complex to be mentioned is known as the Gasoline Tunnel. Located at the NW corner of the Malinta Central System, it consisted of 6 laterals containing large metal storage tanks for gasoline. A central shaft from the laterals ran east-west out to the west side of Malinta Hill. There was one ventilation shaft out to the hillside and the tunnel system was fully concrete lined. The 1934 map shows the Gasoline Tunnel to exist at that time but it must have been incomplete. The tunnel entrance had a date of 1934 but the RCW released by the Corps of Engineers was not issued until August 4, 1936.

RCW for the Malinta Gasoline Tunnel

Enlargement of the RCW Malinta Gasoline Tunnel blueprint

The RCWs indicate when construction of all sections of Malinta Tunnel was completed with the exception of the South System. I have no RCW for it. Is this simply because (1) I do not have that document, (2) it is lost in some archive or (3) it never got issued by the Corps of Engineers. Additional construction was obviously completed and there may have been periods of inactivity but I know that work continued in the South System even up until wartime. Reason #3 may be correct in that work never really ceased here. The last detailed map that I am aware of is dated July 2, 1940. As of that date, eleven South System laterals were partially complete.

This detailed map dated July 2, 1940 is interesting as it overlays the old and new location of the South System and gives an overall view of the whole complex. (map courtesy of armyjunk).

Fears of an upcoming war would soon bring the US Navy into the picture adding some confusion as to who controlled what SW tunnel space. The Navy expected to lose Cavite’s base facilities when war came so in 1939 it released funds to the Army Engineers. They were to drive 4 tunnels into the south-west side of Malinta Hill and be connected by a shaft to the Army’s South Tunnel Complex. (info from Corregidor, ‘Saga of a Fortress’ by the Belote Brothers). These tunnels would become HQ of the 16th Naval District.

The Navy tunnels initiative had little effect on the Army’s Malinta Tunnel system with one possible exception; did the QMC South System lose its southern entrance to the Navy? What we believe to be tunnel Queen does connect to the shaft heading to the south entrance. Whether due to secrecy or inter-service rivalry, can you imagine Army personnel wandering through secure Navy tunnel areas to get to the south entrance? I doubt it. Unfortunately, details of the secret Navy tunnels are scarce. Even today I know of no Navy or Army Corps of Engineer blueprints for them.

A discussion of the Malinta Navy tunnels is located here: http://corregidor.proboards.com/index.cgi?board=talk&action=display&thread=852

For further reading, see Corregidor.org forum:  DISCUSSION ABOUT THE NAVY TUNNELS

The possible loss of the SW Malinta entrance to the Navy may be one reason for the construction of a new entrance from the QMC South System out to the South Shore Road. This road passes along the south side of Malinta Hill between Bottomside and Tailside. Another reason could have been the QMC’s need for a relatively straight tunnel which would allow for easy transport of materials to and from the storage laterals. The entrance is angled towards Bottomside which would have helped in the moving of longer items such as torpedoes in and out of the QMC tunnels. When this work was undertaken seems to be unknown but would have been started after July of 1940.

A project that seems to have not been recorded was the transformation of the North System from the purpose of storage to a Hospital. This would also have taken place after July of 1940. A major task would have been the addition of water and sewage facilities. I expect that this is the reason the two rear ventilation shafts were enlarged considerably beyond their original 4 ft. x 6 ft. size. In the floor of both shafts you can see a drain pipe that runs the full length of them. At the north end of both shafts, horizontal mini tunnels were dug extending the drains to outside the tunnel. Today the eastern one is collapsed but the western one still exists. A drain pipe can still be seen embedded in the floor of that small shaft.

Two curious features are present in the Hospital. First, both the east and west end ventilation shafts have what appears to be the start of two new laterals that are not shown on maps. One facing west goes into the rock about fifteen feet or so then stops. The second one facing east ends after only a few feet in a complete collapse so it is impossible to determine how far it went. We see no indication of it at the expected location on Malinta Hill outside the tunnel.

Second, these tunnel systems were constructed with a slight grade to aid in ventilation and drainage. For example, the Malinta Central System has a grade of 4.08% sloping down towards the west. One Hospital lateral near the NW corner has a false floor that is especially noticeable at its western end. This appears to give that lateral the unique feature of having a level floor. Dismissing rumors of hidden treasure, my guess would be that this was the operating theatre where the pooling of blood due to a slanted floor would not be a good thing. No one really knows the answer.

In 1941 with war approaching, Washington’s purse strings were starting to get loosened and long delayed projects found approval. One such project was for the gas-proofing of Malinta Tunnel. Over a half million dollars was allocated for this but it never happened as very little material arrived before the start of the war.

If you omit the missing ‘new’ south entrance and the Hospital mini tunnels (and a few other minor details) then the 1940 blueprint is an accurate depiction of the Malinta Tunnel we know today.

This map is a good overview of the Malinta Tunnel System. There are minor errors but it is generally correct. (Modified map from ‘The Hard Way Home’ by Col. William C. Braly)

In the spring of 1941, Maj. Gen. George F. Moore became the Harbour Defense Commander. It was under his watch that Malinta Tunnel would be put to the use that it was intended for twenty years earlier. Probably the most fitting tribute to this tunnel complex came from him when he said “Without the shelter afforded by the Malinta Tunnel…organized defense of the Philippines would have collapsed in its early stages”.

For me, Malinta Tunnel will always be one of the most interesting places to visit on Corregidor Island. Stories of hidden gold and ghosts have nothing to do with it. The information written above speaks only of cavities carved into the rock; there is no mention of the few thousand people who either temporarily lived here or who died within these passageways. History is the real attraction and it lurks everywhere you go.

  GO TO PART TWO...

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