A couple of years after we bought Chestnut we were heading up the Shroppie towards Chester when we started to sink. At least that was one possible explanation! We were going down a flight of locks when Chestnut caught on the side of the lock as it was emptying. This is not an unusual occurrence; many locks have bits of brickwork sticking out of the lock wall, and if you are unlucky one of the strips along the side of the boat catches on it. What happens, as the water level drops from under the boat, is that the boat rolls away from the lock side and falls away from the obstruction. But not before a lot of crockery and implements have fallen off the shelves.
But in our case we found the carpet wet all along the side of the boat, further investigation showed the water was coming up from under the floorboards along their edge.
And that meant there was water in the bilges under the floor.
First thought, of course, is that the incident in the lock had broken a weld on the baseplate and water was now leaking into the boat.
Luckily there was a large hole in the floor behind the fridge for this reason, so we were able to look into the bilges to see what was going on. There was water, so we pumped out what we could and waited – it got no worse. So the boat was still water tight!
Over the next few weeks we removed the floor boards in the lounge to see exactly how the bilges were constructed. Every three feet or so along the length of the boat are steel struts with wooden joists on them. The floor boards are screwed to the joists. The space between the joists are entirely filled with bricks, ordinary internal house bricks. They provide the ballast that keeps Chestnut upright. This means the bilges are about 5 inches deep and completely filled with 4 inch bricks. So there is not a lot of room left for any water to leak into.
So we drilled a 4 inch access hole in the corner of every three foot space, pumped out the water and waited for it to dry out.
And then waited to see under what conditions it filled up again.
Eventually we figured out that water was only getting into the bilges when we filled the water tank. And even then only when we let it overfill. To fill the water tank most people stick a hose down the tank filler, turn on the tap, and go for a cup of tea. It can take half an hour to fill a tank, so there is no point watching it, and once it is full the excess water simply spills into the canal. Or in our case into the bilges.
Chestnut’s water tank is stainless steel, but there are two fittings into the top of the tank, the filler and the breather (the breather lets the air out when water is going into the filler). However none of the fittings seem to be leaking, so the current theory is that the welded seems along the top edge of the tank itself must be leaking. But to check this we need to remove all the fittings and most of the bedroom furniture and pull the tank out from under the well deck. Something for the future.
To help cope with the tank leak Chestnut now has a water tank gauge and a leak detector.