Japanese tunnels, Diocesan Boys School [????- ]
These tunnels were the center of attention in early 1946 - when they exploded!
The tunnels were dug into the slope on the southern edge of the Diocesan Boys School (DBS) campus, near to Argyle Street. The tunnels would have been well known to the school at the time, as the school staff had been pressed into digging the tunnels by the Japanese. The DBS website notes:
The school was occupied by the Japanese in the year 1941. Most of the personnel (including Mr. Goodban and the staff) at school were jailed and made to dig an underground chamber to store the ammunition of the Japanese. The building itself was transformed into a military hospital (Kempi Tai to serve the Japanese soldiers).
It might seem strange to store large quantities of explosives near to a hospital, but maybe they thought the area would be less likely to be bombed during air raids?
After the war, an immeadiate task for the returning British forces was to make safe the explosives and ammunition left behind by the Japanese. They knew of this tunnel and had already removed a large quantity of explosives, before deciding to leave the rest under observation. By the end of 1945 it became clear that someone was trying to steal the remaining explosves, and it was decided to finish the removal work.
On the day of the explosion, it was noted that five tons of cordite were removed by the government workers. Unfortunately that revealed a previously unknown side-tunnel, also packed with explosives. The decision was made to seal that tunnel, as it was considered too dangerous to move the explosives. But that never happened, as later in the evening there was a huge explosion.
The three houses at 117-121 Argyle Street took the main force of the explosion, with four people killed there. Fortunately, the earth above the tunnel absorbed a lot of the blast, preventing further loss of life.
This report at the time gives an idea of the force:
The road to DBS was completely blocked and Argyle Street was covered with earth and mud from the railway bridge to St George's Mansions. Peace Avenue was deep in earth along its entire length.
It seems the tunnels were never filled in completely, as they still had to be considered during the recent construction of the new DBS primary school:
The site slopes over a disused tunnel and is surrounded by high and steep slopes with a main railway track running alongside. Our cost-effective civil and geotechnical solutions supported the building planning to overcome these difficult site constraints and also avoided extensive disturbance to the existing natural vegetation and topography. They included an innovative exploratory method using CCTV to assess the exact alignment and condition of the tunnel to eliminate short term risk during piling as well as to ensure long term site safety.
Here are the newspaper clippings from January 3, 4 and 5, 1946, reporting the explosion:
Please leave a message in the comments below if you know any more about the history of these tunnels.