No.3 Dock Disaster
Thanks to Desmond Brown for the following recollection:
In the Dockyard a caisson performs a similar task to lock gates on a canal, the big difference being that a caisson is moveable and floats like a ship.
When a vessel needs to be dry docked, the dock is first flooded, the caisson is then removed by pumping out the water inside of it. When fully afloat it is moved by capstan and cables to the outside wall leaving the entrance to the dock clear. The vessel is then towed into the dock and the caisson is returned to the entrance and guided into position. Water is then pumped into it tanks to sink it and form a watertight seal. It is then used as a walk and road way. The water in the dock is pumped out with the vessel being docked on oak blocks at the same time.
On this particular day the tide was very high and the caisson in No 3 Dock became buoyant and lifted out of its seating. The river water poured into the dock like a huge tidal wave carrying the caisson with it. The submarine HMS Talent in turn floated and was carried out into the river with the returning surge of water.
Four men died as a result of the incident.
The following is an account of my personal involvement.
On 15 December 1954 I was employed as a Shipwright Diver in Her Majesty’s Dockyard Chatham. I was 26 years old and had been diving for three years during which time I had carried out various types of underwater work. Nothing up to that day, had prepared me for what I was about to experience.
It was mid-afternoon and fellow Diver Bill Fletcher and I were working on No 7 Slip when I noticed a sudden and unusual surge of tide. I looked around to see what kind of vessel would cause such a miniature tidal was but there was nothing in sight so I continued with my task.
A little later Bill Hanniford, our Cleaner in the Diving Store, which was situated on the corner of No 5 Machine Shop, came over as fast as his elderly legs could carry him. He had received a phone call from Tommy Gillan, our Chargeman. I was to collect my gear (woollens and diving suit) and get up to No 3 Dock immediately. I assumed that, as submarine HMS Talent was in dry dock there, the diving job would be river side.
Accompanied by Bill Fletcher I walked up on the river side back of the slips, crossed over No 4 Dock caisson to the entrance of No 3 Dock. On arrival, being a fairly observant person, I noticed the caisson was missing. There was a crowd of workmen, some of whom I knew, standing at the end of the dock. On enquiring as to the whereabouts of the caisson they pointed to the head of the dock. Where was Talent? They pointed across the river to where she lay aground on a mud bank. We hurriedly made our way up the side of the dock where it became all too apparent that a disaster had occurred.
The caisson was lying near the top end of the dock and leaning precariously toward the centre. The water around it was covered in debris. We proceeded to the head of No 3 Dock and saw the diving party was already there unloading the pump and all the equipment a diver is encumbered with. Tommy Gilllan hurried over to me and told me to go down and check whether the caisson was lying hard on the dock bottom. If it wasn’t, things could get much worse.
All the diving gear, helmet, weights and boots etc had been assembled on the dock steps close to the water. As I dressed I could not take my eyes off the caisson and the way she was leaning over. Not too much but enough to present a real danger with the tide on the turn. Any movement in the water may cause the caisson to lurch even further over. Bill Fletcher had in the meantime boarded the caisson (a brave act in the circumstances) and rigged a shot rope from the caisson to the dock bottom. Divers always descend on a shot rope to control the speed of their descent.
How I got to the caisson is rather hazy. Bill must have rigged another line from the caisson to the dock steps to enable me to pull myself over on the surface. Anyway, I reached the shot rope. It seemed a straightforward operation. To go down, check how the caisson was standing, then return back up the shot rope to be pulled back to the steps. Piece of cake …
I signalled my attendant, Jack Gregory (a first class man who you could entrust with your life) that I was going down by giving him the thumbs up, then started to lower myself gradually adjusting my air supply accordingly.
Then the troubles began. All the oak blocks, which were chained together, had been swept up in the tidal fury to the end of he dock and were buoyant and I had dropped right down on top of them. Getting down to the dock bottom was difficult as the blocks were swirling about me as I descended. I was struggling to get through between them and the caisson.
In a ticklish situation you are trained never to panic or to work too hard underwater because you produce more CO2 than the air you receive. You wait until the position you are in is completely hopeless … then you panic!!
At last I felt my feet on the dock bottom and found the caisson was also hard on the dock bottom near to the dock side. I had to reach the other side of the caisson, which was only about twelve feet wide. Goodness knows how I got there.
I found it was again hard on the dock bottom. I did not venture too far down the side of the caisson remembering that it was leaning over but I went far enough to confirm that it was solid all the way along.
Now to return to the surface.
I was breathing heavily, which is not a pleasant experience in a diving helmet. Normal procedure was to stop what you were doing, call for more air (two pulls on the air pipe) and wait until you are breathing normally but I was not particularly enamoured with the prospect of staying there, so I decided that the best way to the surface was to be pulled up. I signalled on my breast rope with four pulls “I’m coming up” followed by two short pulls “pull me up”. Not an attendant’s favourite signal.
The way back up was just as bad, if not worse, than, going down. Being pulled up through a mass of dock blocks is not the most envious of situations, mainly because I had no control. I worried in case my breast rope or any of the connections on my helmet got caught in the chains. My airpipe was alright being designed to float from the diver straight upwards. It was a struggle to stay upright though.
At last I reached the surface and was pulled up to the steps (good old Jack). He removed my front glass and I gulped in lungfulls of fresh air. He then untied my weights and removed my helmet and I just lay there on the steps gasping for breath.
The voice of the Senior Officer, Mr Roach, above me enquired as to the state of the caisson. I managed to convey to him that the caisson was solid on the dock bottom. I lay there for a few minutes longer and gradually began to calm down with the satisfying knowledge that the task was complete. I began to get dressed and Tommy came over for a report. When I informed him of the state of the dock bottom he couldn’t believe it. We remained on the dock all night and all next day working as required.
We continued diving operations over the next few weeks, first off, searching for bodies. Over the next months we salvaged the caisson and replaced it, working the most unearthly hours imaginable. I still shudder to think that one the week before at high tide I was diving on the outside of the same caisson. My good friend Alan Rayner assured me that I would have been OK because I was wearing a diving suit!!
Some time later, we were discussing the disaster and Tommy Gillan said to me “Des, you know you were lucky that day”. I enquired as to why. “Well” he said “if that caisson had toppled over, you would have been a goner”.
