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San Francisco Maru

The San Francisco Maru was a passenger/cargo vessel built in March 1919 by Kawasaki Dockyard Co Ltd in Kobe, Japan for Kawasaki Dockyard Co Ltd. Launched on 1 March 1919 and placed into service on 14 March 1919, the new ship was 5,831 tons gross, 117 metres (385.0 feet) long and 15.5 metres (51.0 feet) wide. It arrived in Chuuk on 5 February 1944 as part of a convoy but had remained there when the convoy sailed on the 12th.

San Francisco Maru Drawing

Technical Data

  • Tonnage: 5,864 tons gross

  • Length: 385ft (117.34m)

  • Width: 51ft (15.54m)

  • Depth: 36ft (10.97m)

  • Draught: 27ft (8.16m)

  • Engine: 1xrecoprocal Steam (Coal)

  • Horsepower: 3,946hp

  • Max Speed: 14.27 knots

  • Service Speed: 10.00 knots

  • Launch Date: 1st March 1919

  • Entered Service: 14th March 1919

  • Builder: Kawasaki Dockyard

  • Owner: Yamashita Kisen

Today the San Francisco Maru sits on a sandy bottom with the bottom of the stern at 57 metres). The bow end is a bit deeper, say 65 metres and the sand on the port side is about 63 metres.

This passenger/cargo ship sunk upright fully loaded with cargo thus is often called 'The Million Dollar Wreck'. Deck cargo includes both trucks battle tanks. Hold cargo includes mines, torpedoes, bombs, artillery, anti-tank, small arms munitions, aircraft engines & parts & oil/gasoline drums.

As you descend from the surface you can see nothing but blue water. It takes about 60 secs before you first see the dark outline of the superstructure approaching from the depths below. As you reach the superstructure a quick check of your dive computer reveals a depth of 45m and 8mins before the NDL.

From here you can already see the 3 tanks on the deck, the forward gun, and the tankers in the No.2 hold. You continue your descent to the deck at 50m and quickly circle two of the tanks on the port side. You now have only 4mins to the NDL.

Swimming forward you pass over the No.2 Hold and have a quick look at the 2 completely intact fuel tankers. Having past over No.1 Hold you reach the forward gun after a 60sec swim. You circle the gun swimming out over the bow of the ship. This is eerie in the half light at 50m. You can just make out the sandy bottom a further 15m below at 65m.


By this time your computer starts beeping, signalling only 3mins to the NDL.

Swimming back towards the superstructure you would notice the NDL time now only 3mins away. Reaching No.1 hold you see the beach mines stacked to the top of the hold, and notice some have been taken. You descend into the space were these mines used to be taking your depth to 53.5m.

Being so close to tonnes of explosives that have been sitting in this spot, 53m below the surface, for 60yrs makes your heart race. You ascend out of No.1 Hold and head aft.

Arriving at No.2 Hold you descend into it and take up the driver’s position in the starboard side tanker. Your dive buddies think you’re ‘Narked’ as you simulate driving the fully load fuel tanker.

You're now past the NDL and you're required to do 1 Deco stop.

It’s amazing to see that after 60years the tyres on the trucks are still in almost perfect condition and still look inflated.

There is still time enough to swim past the tank on the starboard deck before beginning your ascent. As you past the superstructure you notice you now have to do 2 deco stops.

Total bottom time 11mins including descent. Total ascend time 25mins including stops for 2mins at 20m, 5mins at 10m and 10mins at 5m.

What an absolutely awesome experience – one that I have been fortunate enough to do 3 times.
Dr Shane Currie
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