Log entry 2 of 4 · Water
Water points, a tank gauge that lies, and a week of washing-up
The boat carries a fixed amount of fresh water in a steel tank under the front deck, and every crew runs out at least once. After the third time it happened to our household, I started writing down how much we used and where we filled, and the numbers changed our habits more than any amount of nagging in the log.
- First written up
- 6 July 2025
- Last amended
- 30 August 2025
- Time to read it
- Roughly 7 minutes
- Home waters
- Regent's Canal and the Lee Navigation
Stretch 1
How much the tank actually holds
The previous owners told us the tank held about five hundred litres. That turned out to be roughly right for a completely empty tank filled to the brim, which is not how anyone uses it. In practice the pump starts spluttering with something like forty litres still in the bottom, because the pickup sits above the floor of the tank and the boat usually trims slightly towards the stern. At the top end, the last ten or twenty litres take ages to go in because the filler neck backs up before the tank is truly full. Our usable figure is closer to four hundred and twenty.
Four hundred and twenty litres sounds like a lot until you watch where it goes. A shower with our pump and a careful person is between fifteen and twenty-five litres. A washing-up bowl is five or six. The kettle barely registers. The toilet is a cassette with its own small flush tank, filled separately, so it is not part of the sum. Two adults showering daily and cooking properly get through the tank in three and a half to four days, which matters on a long weekend with no water point on the way home.
What surprised us most was how much the weather mattered. In the hot week at the end of June we ran through water nearly half as fast again as we had in March, mostly in showers, drinking water and rinsing out the cool box. The log now has a line for water at the start and end of every trip, and the summer entries are noticeably shorter on patience.
Stretch 2
The gauge that lies and the stick that does not
There is a gauge on the wall by the galley. It has a needle, a green zone and a red zone, and it is wrong in both directions. It reads full for the first third of a tank, then drops quickly, then sits at a quarter for a day and a half before suddenly reading empty. We suspect the sender inside the tank has a float that sticks, but getting at it means lifting the front deck boards, and none of the four households has volunteered for that job yet.
What we trust instead is a length of dowel with notches cut into it, which lives in a clip beside the filler cap. One of the other households calibrated it on a wet afternoon by filling the tank from nearly empty, counting the minutes at a tap with steady pressure, and marking the dowel as it went. It is crude, and you have to unscrew the filler cap on the front deck to use it, which is no fun in the rain. But it tells the truth, and the log now records dipstick readings rather than gauge readings.
The one trick worth passing on is to dip the tank at the same time of day and with the boat level. With two people standing on the back deck and the boat tipped towards the stern, the reading at the front drops by a notch. We dip first thing in the morning, before anybody is up and moving about.
Crew checklist
- Dip the tank with the boat level and nobody standing on the stern
- Write the reading down at the start and the end of every trip
- Treat the wall gauge as decoration until somebody fixes the sender
Stretch 3
Where we fill, and how long it takes
Water points on the London canals are taps on posts or in small cabinets along the towpath, usually near a lock or a service block. Some have good pressure and fill our tank from half in twenty minutes. Others trickle, and filling from low can take the best part of an hour. The difference is not marked anywhere, and we learned it only by keeping notes. The back pages of the paper log now list every water point we have used, with the time it took and whether there was room to moor while filling without blocking anyone.
The best habit we adopted is filling on the way out rather than on the way home. When a trip ends, everyone is tired and wants to get the boat back to the mooring, and nobody wants to sit at a slow tap for forty minutes. So the tank gets topped up at the first water point of every trip, even if the dipstick says it is three-quarters full. The crew after us then starts with a full tank rather than inheriting our emptiness.
On busy weekends there is often a queue. The etiquette we have picked up is simple: fill, do not start the laundry while tied to the water point, move off as soon as the tank is full, and if somebody is waiting, tell them roughly how long you will be. We carry our own hose with a couple of spare connectors, because the fittings on the taps vary and some of the hoses left hanging on the posts are not ones we would drink from.
Stretch 4
A week of washing-up in the summer rota
Our longer summer trip this year was a week, split between the Lee and a few days in east London, and it was the first time we managed a full week without an emergency water run. The routine that did it was unglamorous. Washing-up happened once a day, in the evening, in a single bowl with a second bowl for rinsing, and the rinse water went on to the next morning's pans. Showers were short and taken every other day, with a strip wash in between.
We also started carrying two ten-litre containers of drinking water filled at home before the trip. They sit in the front well deck and are only for drinking and the kettle. It seems like a small thing, but it separated the water we cared about from the tank water, and it meant that the moment the tank got low, nobody had to worry about tea.
None of this is how a liveaboard boater would describe their water habits, and people who live on their boats all year have far better systems than ours. We are part-timers with a shared tank and a rota. But the other households have taken to the dipstick and to filling on the way out, and for the first summer since we bought our share, the log does not contain a single entry in capital letters about finding the tank empty.