fresh water tank capacity

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woodscrew

Senior Member
Joined
Feb 14, 2016
Messages
100
Location
USA
Vessel Name
Northern Star
Vessel Make
Bristol 42 1970
I am getting ready to order new additional fresh water tanks for my Bristol 42. Current capacity is only 90 gallons. We plan to start cruising/living aboard full time this fall and that is not enough. (Being stingy with water, although not on rations we seem to use about 15 gallons a day). It looks like I can comfortably fit two additional tanks of about 85 gallons each for a grand total of 260 gallons. What is everybody else carrying? I could get another 50 gallons under the new (luxurious) queen bed I'm building as part of a major refit of the aft stateroom.We'll be spending a lot of time on the hook while cruising, with some long interludes at marinas in warmer climes this winter.
 
Do you have a water maker aboard? If yes what is the purpose of adding more tanks vs making water? If not why not to install one instead of adding such a weight of water?
 
Adding 170 gallons would be super, but as already mentioned, weight can have issues. Before making a commitment, you might consider scrounging 170 one gallon water jugs, filling them, then placing them in the boat to see how it effects your free board and trim. On the other hand, having all the capacity doesn't obligate you to use all the capacity if it negatively impacts stability. My boat has a 300 gallon water capacity. It's very nice to have on long trips, but I rarely fill up for shorter ones as there is some impact to the trim of the boat.

Ted
 
Nice looking boat. Our 43 ft Mainship carries 250 gallons. This summer my wife and I made it about three weeks between fill-ups.
 
I agree, 90 G just doesn't cut it if anchoring out much.
I have 356 USG in two tanks. Plus a Spectra Newport 400 watermaker. You aren't always in clear water to use the watermaker (without plugging filters quickly) I never do any water rationing.
 
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woodscrew, since you're not going to be attached to the dock, you need maximum water capacity. You don't have to use all the capacity, and empty tanks weigh pretty much nothing. If it affects your trim but you're anchored in a harbor then it is meaningless.

Watermakers are relatively complex machines compared to say a pressure water pump or a windlass. Complex things break. You don't operate them in dirty water and eventually you will find yourself anchored in an area of high bacteria counts for weeks on end (think Southern California after heavy rains). They also cost about $5k and up, which perhaps is not in your budget.

It's also REALLY nice to be able to do laundry every now and then. Today's digital inverter, European style machines run off a 1k inverter and don't use too much water.

I had 440 gallons on my last boat and it was fantastic. The next boat will have even more capacity, with or without a watermaker.
 
Lots of "ifs". If you are going to be anchoring out extensively, if you are going to spend months at a time on the boat, if you are going to be in a location where there is rainfall.

If so in adding additional tanks you may want to reserve a tank for rain water. With a separate pump you could use the rainwater for showers, for flushing the head, etc. I have avoided the complications of separating my two tanks and installing a separate pump and instead just use jugs of rain water for cleaning etc.

More and more cruising boats are installing watermakers so be aware of this option. A watermaker should be activated every five days or so (unless pickled) so the 95 gallon tank you have would be sufficient. However, the second tank could be useful.
 
Thanks for the replies. I considered a water maker, but since we'll be cruising the ICW and hopefully the Loop one day where clean water if readily available for free I decided against the cost and complexity of one. As a friend of mine said nothing's simpler than sticking a hose into a tank.The weight is not an issue, in fact the boat has 4000 pounds of lead ballast aboard which can be shifted to trim up. These hulls were designed (by Eldridge McGinness) for commercial fishing to carry 10,000 lbs of fish. I moved 1000 lbs from forward of midships to the stern and the boat settled by just over an inch and is stiffer and rides better. I am expecting the added weight of full tanks aft to improve that trend. I doubt we'll be more than two weeks without pulling into a marina for fuel and groceries etc. I think I'll put in the two 85 gallon tanks and see what happens.And build the bed with easy access to fit the other tank if needed. Could get another 60 gallons on the centerline amidships down in the bilge too.
 
I am getting ready to order new additional fresh water tanks for my Bristol 42. Current capacity is only 90 gallons. We plan to start cruising/living aboard full time this fall and that is not enough. (Being stingy with water, although not on rations we seem to use about 15 gallons a day). It looks like I can comfortably fit two additional tanks of about 85 gallons each for a grand total of 260 gallons. What is everybody else carrying? I could get another 50 gallons under the new (luxurious) queen bed I'm building as part of a major refit of the aft stateroom.We'll be spending a lot of time on the hook while cruising, with some long interludes at marinas in warmer climes this winter.



One of the many design features on Great Harbour trawlers is large tankage. We have 480 gallons of water an also a 320 gallon holding tank. When you add 1380 gallons of fuel and burning only 3 GPH range is not an issue for the cruising we do. We love not feeling like we have to ration water. The tanks are built into the hull structure so the center of gravity is also low with no Corrosion issues or condensate fuel issues. We also can make water but we don't now given we are cruising on the inland river system but we plan some blue water time in the years to come so the water maker will continue to make water a non issue.

IMG_1049.JPGIMG_1048.JPG
 
Woods screw

We carry 400 gallons. More than enough even with guests on board. Adding more tanks seems logical. You can always add a water maker later.

Be sure that any tanks you add can be gravity drained to bilge via an easy access valve. This allows you to flush the tanks every now and then. Also add sight tubes and large diameter fill pipes. The fresh water pump manifold should be set up to draw from any tank.

Nice boat and smart thinking on your part.
 
Sunchaser,
My thoughts exactly on draining tanks. My paltry 90 gallon tank setup gets drained every fall, filled, bleached and drained in the spring. All into the bilge and pumped out. Makes for a clean bilge.
Woodscrew
 
We carry 200 gallons of fresh water in 2 tanks and that works for my wife and I for about a week or so between fillups.

Ken
 
I find the different perspectives on this to be interesting. I come from the world of sailing. Lots and lots of people cross oceans and sail around the world in sailboats with less than 200 gallons of water capacity. A friend of mine was one of a total of three crew members who sailed across the Atlantic, spent a few months in the Med, and then returned, all in a sailboat (with no watermaker, mind you) that had a capacity of just a tad more than 100 gallons of water. In fact, with sailboats, more than about 100 gallons is usually considered "a lot."

Not making any judgments here. Just musing on the differences in perspectives, as I said.
 
Our capacity is 60 gallons.


Different boats and different cruising styles will require different water capacity. Someone mentioned doing laundry. If your boat is 28' long, you probably don't have a clothes washer on board so that's a lot of water capacity that you don't need.


Some people like to take long, hot showers while others get by with getting themselves wet, turning off the water, lathering and turning on the water to rinse. That's more water capacity that you don't need.


The OP talks about the ICW and the Great Loop. He will never be far from a source of potable water.


If he wants to increase capacity and his boat can handle it, fine. The warning is to install and plumb the tanks to where the center of gravity does not shift as water is consumed.
 
We carry 400 and use it like we're at home, so the water maker is always running.
 
We carry 300 gallons plus a water maker for 2 adults and a dog. The dog gets a good rinse after every beach walk as does the boat after a windy day on the water.
 
600 gal and a watermaker that need repairing!
 
Thanks for the replies. I considered a water maker, but since we'll be cruising the ICW and hopefully the Loop one day where clean water if readily available for free I decided against the cost and complexity of one. As a friend of mine said nothing's simpler than sticking a hose into a tank.The weight is not an issue, in fact the boat has 4000 pounds of lead ballast aboard which can be shifted to trim up. These hulls were designed (by Eldridge McGinness) for commercial fishing to carry 10,000 lbs of fish. I moved 1000 lbs from forward of midships to the stern and the boat settled by just over an inch and is stiffer and rides better. I am expecting the added weight of full tanks aft to improve that trend. I doubt we'll be more than two weeks without pulling into a marina for fuel and groceries etc. I think I'll put in the two 85 gallon tanks and see what happens.And build the bed with easy access to fit the other tank if needed. Could get another 60 gallons on the centerline amidships down in the bilge too.


From your description of your boats mission, you're making a sound decision regarding adding tanks and holding off on a watermaker for now. It also sounds like you'll be using the space unbder your being constructed bed for the tanks, good idea.

Some here will tend to be minimilists regarding water, some not. We spend around a week at a time away from port with our current cruising style. We find that we use around 50 gallons a day of potable water. More if we do laundry at sea. That said we do not think of conserving. We just do our normal activities and let the water work itself out.

The boat carries 200 gallons, and we have a watermaker.

If your cruising style and habbits dictate a watermaker you'll put one in, but for now it's all a big unknown, so I'd go stick with your plan and see how it shakes out.
 
I find the different perspectives on this to be interesting. I come from the world of sailing. Lots and lots of people cross oceans and sail around the world in sailboats with less than 200 gallons of water capacity. A friend of mine was one of a total of three crew members who sailed across the Atlantic, spent a few months in the Med, and then returned, all in a sailboat (with no watermaker, mind you) that had a capacity of just a tad more than 100 gallons of water. In fact, with sailboats, more than about 100 gallons is usually considered "a lot."

Not making any judgments here. Just musing on the differences in perspectives, as I said.

It seems that to many sailors, the sailboat comfort profile is more akin to camping than for trawlermen who prefer comfort over simplicity and efficiency. It's the comfort level of trawlers that draw me to them.
 
It seems that to many sailors, the sailboat comfort profile is more akin to camping than for trawlermen who prefer comfort over simplicity and efficiency. It's the comfort level of trawlers that draw me to them.

:thumb:
 
1000L/260 gal, in 4 tanks, no watermaker, has proved adequate for over a week.
 
Boomarang (my Fales 30 Trawler) 2x35=70 gal. - proved adequate for weekends or a little longer for a couple.

Pelago 1x52 gal. - small but OK for day cruising/fishing or an overnight. Seem to use water faster, but normally have more guests aboard and a fresh-water fish cleaning station.

If any longer cruising is envisioned, I think a watermaker will be in order . . . . I want to keep it as light as possible.:D
 
1000 gallons, haven't used the boat yet so that's all I can say
 
I'd go for max capacity, assuming the space isn't critical for other things. I can't see any way to have too much water. It just adds flexibility and increases comfort.

We have a 600 gal tank and 1000 gal/day water maker, so use water at will and it's really nice.
 
300 gallons plus two watermakers putting out a combined 65 gallons / hour. When in an anchorage, we make water only on the incoming tide, and generally only once per day, but that is enough to keep fill the tank. Enough water for long showers and boat washdowns (and no spots with RO water).
 
As ex sailors (2) 60 gal FW tanks last as long as it takes to fill the waste tank, about a week or 10 days.

Big water tanks are needed for transits off the shelf in Blue water , or the Bahamas where the water is crap or expensive , but hardly for inshore cruising.
 
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