Fitting out a boat of any size can quickly get pricey, so Zoran Glozinic repurposes some ‘non yachting items’ for a small sailing cruiser’s new plumbing system

The galley I planned to have in my small yacht, Old Duck, was to be a simple portable box, equipped with bare necessities, but even having fairly limited cabin space I still wanted to have a boat water tank and sink.

There was already a small sink in place on the starboard side across the ‘galley’ area.

A boat water tank and sink on a yacht

The new look galley with sink in worktop and boat water tank underneath it. Credit: Zoran Glozinic

The size of it was adequate, except by being very shallow it was not of any real-life use, particularly at sea.

What I found interesting was the plumbing – or lack of it; the galley sink was equipped with a drain including a seacock and bronze thru hull but there was no water tank anywhere in sight nor a pump/tap installed to get any water into the thing in the first place.

Galley remodelled

I began by removing the existing sink, together with its plumbing, removed the thru-hull fitting and permanently closed the hole in the hull where it was installed, fibreglassing it with resin and chopped strand mat.

I wanted to have a sink without a drain, so I could take it out and, if needed, use it in the cockpit or on shore.

A blue and white Vivacity 20 yacht moored in a marina with fenders hanging from the sides

Zoran Glozinic’s Vivacity 20 Old Duck. Credit: Zoran Glozinic

I tried to find a replacement sink with the same or a similar footprint, but at least twice as deep.

My search was not successful; some stainless steel sinks I found would have fitted, but all of them were way outside my budget.

For a while, the ‘sink project’ stayed on the back burner, while I kept busy doing other things around the boat.

Eureka moment

One afternoon I decided to make some order out of the constant mess inside the cabin, which at the time was full of tools, paint cans, various pieces of equipment, boxes with fastenings and the other paraphernalia usually found in the middle of an old yacht restoration project.

The day before I’d bought a dozen rectangular recycling bins in two sizes.

By pure chance I found out that the smaller of the two could fit into the opening where the original sink was installed.

A blue boat sink

A recycling bin was an almost perfect size for the existing sink hole. Credit: Zoran Glozinic

It was deep enough and it needed just a slight enlargement of the existing opening in order to fit there properly.

What was even better, these bins were stackable, so I could keep two or three of them stacked in the same worktop aperture and use them when doing dishes – one for washing, another one for rinsing.

Stacked together in the sink they’d only occupy just a bit more vertical room, compared to the sink alone.

A hole cut into a work top with a new sink

Marking the hole for cut in order to move the new sink so there’d be room for a tap. Credit: Zoran Glozinic

I made a cut-out template using strips of thin plywood which I hot-glued together around the outside perimeter of the bin.

The opening for the new sink was enlarged and cut close to the inboard edge of the sink cabinet in order to provide necessary space for the installation of a hand pump tap if I decided to go that way.

That resulted in a longer opening than needed so I built a new countertop to hide it.

Storage tank

Having solved one part of the problem – I now had a deep and removable sink – I next turned my attention to water storage.

It was more than obvious that I had no space required to install a large-capacity water tank as I had on my previous boats, but I had few ideas on my mind.

When not in use, the sink is covered with a multipurpose cover board. Credit: Zoran Glozinic

When not in use, the sink is covered with a multipurpose cover board. Credit: Zoran Glozinic

My first thought was to do without a pump and tap and just have a small water container with spigot installed above the sink.

Surprisingly the camping-type two gallon water container with spigot I purchased was just small enough to be fitted above the sink and under the side deck, however after spending some time thinking about it, I decided not to go that way.

Continues below…

One of the reasons for abandoning that particular idea was the fact that even this small container, when full, would weigh 22lb/10kg.

This of course is not that much, but I’d still rather have that weight low down on a sailing boat – ideally below the waterline.

A template to make a boat tank on a blue bag

Ready for cutting the opening to install the water fill and outlet hose fittings. Credit: Zoran Glozinic

But the more important reason was that I’d then not be able to store my portable galley box on top of the sink, because I wanted to keep it there when not in use.

I’d also need to spend time building some kind of enclosure for it, as it would not be ideal leaving it exposed to light all the time.

Nasty things grow in water much faster in daylight.

Exploring options

I thought some more about where I could keep my tank. Ideally it should be in the dark, somewhere low down, easy to access for filling it with water and not too far from the sink – I didn’t want to run a long water hose through the boat.

Soon I realised that the perfect solution was looking straight at me from the very moment I managed to create some order inside the main cabin.

A blue boat tank

The boat water tank installed under the sink, in the larger recycling bin. Credit: Zoran Glozinic

I’d used up all of the recycling bins I’d bought for storing many bits and pieces; one of the larger sized bins ended up under the sink and partially under the V-berth, wedged between the two hull-reinforcing half ribs.

This bin was just wide enough for the water container to fit inside and long enough so its spigot did not have to be removed.

Later on I installed a small wooden block to keep the container from moving back and forth inside the bin, making sure the spigot could not be broken or damaged.

The bin volume was more than 10lt, so should there be a leak from the container, it would be contained inside the bin.

Installing the wooden block to prevent the boat tank from moving

Installing the wooden block to prevent the boat water tank from moving. Credit: Zoran Glozinic

I’d found my ideal water tank location. About one third of the water tank was protruding under the V-berth and it was accessible through one of the existing flush-fitting hatchcovers under the berth cushions.

The rest of the tank was inside the small locker which had the sink installed on top of it. I used the vertical side of the locker next to the V-berth to mount a block of wood which jammed the tank in place so it is well and truly secured.

Even if I managed to turn the boat upside-down, the bin with my water tank inside would, theoretically, stay put.

I decided to have a single point of entry for both the water fill and tap pick-up hose.

polypropylene plates on a boat tank

Inside and outside polypropylene plates installed. Credit: Zoran Glozinic

I fabricated two rectangular plates from thick polypropylene plastic.

Through both of them I drilled one large hole and then, next to it, I drilled another one with a smaller diameter.

The water fill fitting was made from a 2in ABS female adapter hub and male plug.

A piece of copper water pipe was used as a guide for the plastic hose which was to be connected to the hand pump tap.

inside a boat tank

inside view of the boat water tank. Credit: Zoran Glozinic

Without copper pipe, the plastic hose would wander all over the tank, perhaps curling up out of the water – this way it is held in place slightly above the bottom of the tank so I can access the full contents.

Next I marked a rectangular hole on the top surface of the tank. I drilled holes on each corner before cutting between the corners using a very sharp blade.

I inserted one of the polypropylene plates inside the tank and then using another plate and five stainless steel screws I sandwiched the top surface of the tank between two plates.

Water fill with copper pipe (to hold the outlet hose in place) installed. Credit: Zoran Glozinic

Water fill with copper pipe (to hold the outlet hose in place) installed. Credit: Zoran Glozinic

I first pushed the copper pipe through the plates – I purposely made it tight-fitting.

I put a few wraps of Teflon tape around the fill adapter and slowly pushed it in place.

There’s no need for a sealant or glue as this assembly should normally stay above the water level most of the time.

Even if there are small leaks when the tank is full and the boat is rocking, the leaks should be contained within the bin holding the tank.

So far my bin has been bone-dry. The plastic pickup hose for the tap was inserted through the copper pipe and positioned just above the bottom of the tank.

It did not need any fixings to stay in place, the tendency of the plastic hose to resume its previous curvature holds it securely in place inside the copper pipe.

Living with it

The water fill is easily accessed through the V-berth hatch cover and although I do need to use a plastic funnel and a piece of hose, filling the tank is a simple and quick affair.

After a few seasons of using my new sink and water tank I have no complaints about it.

The tank stays firmly in place, the water is always cool and there have been no leaks.

A plastic hose with a funnel

To fill the boat water tank, a funnel with a piece of plastic hose is used. Credit: Zoran Glozinic

At the end of the sailing season, I only need to remove the two wing nuts securing the wooden holding block and pull out the plastic hose going to the tap – then I can remove the tank for inspection and cleaning.

And maybe the best thing of all – this whole affair had the price tag of less than CA$25 (£15).

I already had the hand pump and tap so I’ve not included that in the cost.

I hope this example may provide other readers with some food for thought when trying to implement big boat amenities within a small yacht’s limited space.

Bisphenol A considerations

Back in the day when many of us blithely guzzled water out of lead pipes in our own homes, siphoned petrol into outboards with our mouths, and drove home from the pub, terms such as BPA-free were not in the common vocabulary.

But knowing what we do now about Bisphenol A and its possible long term effects on human health, potable (drinking) water tanks used on boats, or anywhere else, should not be made from plastic containers of unknown material.

With that in mind, I selected a ‘BPA-free’ camping water container for my boat’s water tank.

But using a recycling box for the sink is fine, as it’s never going to be drunk out of and is principally used to catch the excess water when washing up.

A BPA-free camping container with tap was used to make my water tank

A BPA-free camping container with tap was used to make my water tank

Another aspect to consider with water tanks on boats is the bacterial nasties that can grow in still water.

Keeping the tank somewhere dark helps reduce the growth rate, especially if it’s a translucent tank like mine.

For small boats, I’ve always found it’s best to have the water tank removable for filling and cleaning at the end of the season.

Cleaning a water tank can be done with normal household bleach at a very diluted concentration of 50ppm, and if it has got too bad and there is visible growth, such as a green tide mark, a bottle brush intended for baby bottles can really help.

Make sure you generously rinse all of the bleached water through all pipework before there’s any chance of anybody drinking it.

According to usual recommendations, water tanks and all pipework for potable water should be cleaned and flushed twice a year.


Enjoyed reading How to make a budget boat water tank and sink?

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