Watermakers and Harbors

[nwdiver]

Originally Posted by scarlet

I've been reading a book abut a cruising couple, and in the book they state that if you are going to be anchoring or mooring in harbors or mooring fields, a watermaker would be a waste of money. They stated that you couldn't make drinkable water out of most harbor waters in the carribbean, citing sewage.. oil spills, garbage, etc as a reason for not using it. I had never really thought of this, and it certainly makes sense. But, is it true? and, if so.. how can you tell if water is safe to make drinking water from? I was under the assumption that a watermaker filters out not only salt, but other contaminants. If it doesn't do that.. then how would you ever know if your water was safe to drink? Isn't it feasible that you could anchor somewhere, even just a nice small mooring field.. and because of recent use by other boaters, there could be something that taints the water in that area?

I'm just wondering... what are the general safety rules when it comes to making water to drink?

They have made a silly statement unless

1) cruising to them is dock to dock
2) they need fuel for the generator weekly for thier AC and can load up thier water tank while at dock
3) they love handling many 5 gal water jugs in and out of a dinky
4) or they never wash and like the smell....it does happen

[Lepke]

My tanks have been in continuous use since 2011. I do add chlorine to register at the lowest level on a pool test kit. Because I rarely go extended times without making water, I rarely flush membranes. I make water wherever I am, ocean, Alaska, Canada, Columbia River, and various other rivers I can get my nose in. I run 20 & 5 micron washable silt filters and then a GAC, Carbon Block an 1 micron (all 4.5x20) before the membranes.
After the membranes another GAC and a UV light, then the tanks. A year ago I added 3 filters before the galley sink - another 1 micron, GAC & CTO (2,5x10). I have great tasting water. Other boat owners and lubbers comment on it. As long as I keep the silt filters clean the prefilters last seaming forever, more than a year. I haven't changed the galley ones yet. I have a spare membrane housing and use the galley water to flush or pickle spares. My water tests much better than municipal water. And I only test when I'm using questionable sources. Thinking of adding a 2nd UV light after the tanks. I use my RO water for everything, washer, dishwasher, shower, etc. I do notice it cleans clothes better. Tanks have never been emptied since I've had the boat except by normal use. Tanks are galvanized steel.

[a64pilot]

You asked Rich or Tellie, but I can’t help trying to see how much I can get right as I have studied this issue.
First define treat. A filter can remove sediment and chemicals that can give water a taste, but only a few will disinfect, and then at only low flow rates? RO water should have no taste of course, so I assume you mean disinfect by treat?
UV if powerful enough and the water is exposed for long enough a time can disinfect, but of course will not treat for taste nor remove any sediment. Actually if you treat with UV you should first filter as any particulate matter will give places for bacteria to hide from the UV.
UV has zero residual effect so once disinfected with UV unlike chlorine there is no resistance to reinfection.
You cannot disinfect a water tank with UV for several reasons, first of it has any baffles at all the light won’t get everywhere, there will be shadows. Secondly UV light is very readily absorbed by water so it’s range is in inches, about all you can do is UV disinfect at the point of use, during the time of usage.
UV will not sterilize, it will disinfect, the difference I think is sterilization is a guarantee of 100% kill, disinfection means close but not quite 100%?

Nothing I don’t think is as cheap nor as effective as a correct dose of chlorine, however people like me with aluminum tanks are afraid of chlorine, hence me researching UV disinfection.
I have stuck with my Seagull filter, mostly cause it came with the boat, but I believe it has colloidal silver in it, and that I think has some disinfection qualities?
You should filter both before and after you pump. Before a screen to trap big stuff that can harm the pump, but the micron filter after the pump, reason is pumps can pump very well, but can only pull a fraction of what they can pump, and many don’t like being cavitated which a clogged filter may cause.
I assume our fuel filter are before the pump for safety, a leaking filter will suck air as opposed to spraying fuel? Cause I think they should be after the pump.

Rich, Tellie please fill in what I have missed, cause I too want to learn.

On edit
Seagull test data
https://generalecology.com/info/techmemocert

[Pelagic]

Originally Posted by a64pilot

so I assume you mean disinfect by treat?
.

Yes....disinfect is what i meant.

Thanks for your analysis which aligns with my own.

I know from regular internal inspection that my tank is clean and my pre-filter before Par max pump never has any crap in it.
No issue of taste, once I am 100% on to R/O water as I never drink tap water in the Philippines, but I do from the boat.
My key question is whether a UV sterilizer in line on suction side, just sitting there before pump actually does anything, or is it more of a mental thing?


The question for me is whether a

[a64pilot]

My opinion is if your going to do the UV thing, you need to do it after the tank cause while UV will disinfect the water, it has zero residual effect and more than likely if there is growth, it’s in the tank, so you want to treat water after it comes out of the tank. Dumping disinfected water into an infected tank won’t accomplish anything, it won’t disinfect the tank.
However if I could clean and inspect my tank like you can, maybe that would change my way of thinking. Biggest access I have to my tank is if I remove the sending unit, and that is maybe a 2”hole?

I think unless Seagull isn’t telling the truth and faked the testing, that it is sufficient to ensure safe drinking water from a tank that was filled by an RO unit.

[Pelagic]

Originally Posted by a64pilot

My opinion is if your going to do the UV thing, you need to do it after the tank cause while UV will disinfect the water, it has zero residual effect and more than likely if there is growth, it’s in the tank, .

Sorry, my phone updated CF while I was making last post.

Ideally you should have a UV module at each tap point, since bacteria could grow in the standing lines, but that is not practical.

Maybe one at the cold water Galley tap where you fill the drinking water bottles is the best application ?

[SV THIRD DAY]

Originally Posted by Pelagic

Hi Rich and Tellie....
Which method is better?

1..... To treat storage tank water with filter or UV sterilization?

2....Should you put filter on suction side of water pump, or pressure.

Q2:
Pumps like to push better than suck, so I always recommend putting your filter on the pressure side of the pump.

For Q1:
It's all about budget vs risk vs complexity.
You can't beat the Simplicity of adding chlorine to your tanks periodically but if you have aluminum tanks you have to rule that option out. The truth is I think all options can be done in tandem. Filter your dock water going in with a 1 Micron activated carbon filter, then put a UV light at your Galley sink for your drinking water. When it comes to spending the night on the toilet and if you're going to places with poor quality water spending a few bucks on prevention probably isn't the bad idea.

[zboss]

We stopped lugging big water jugs around a while back and we got along just fine. Instead of buying a watermaker, try and get by with an Aquatank II and a 12 volt pump. We drive up to the dock and fill the 60 gallon bag (wish we had bought the 150) with city/dock water, go back to the boat, and pump it into the tanks. No heavy lifting and you get all the water you want in one trip with no worries about dirty harbors!

If you fill your tanks, use the remainder to wash down the boat.

With that said, we did just get a watermaker because when we were last in the bahamas we learned we appreciated spending long periods being still in places without a fresh water supply conveniently located. Combined with our obsession with fresh water washdowns, equipment cleaning, and multiple showers each day... we are heading back there soon.

[SV THIRD DAY]

Originally Posted by zboss

We stopped lugging big water jugs around a while back and we got along just fine. Instead of buying a watermaker, try and get by with an Aquatank II and a 12 volt pump. We drive up to the dock and fill the 60 gallon bag (wish we had bought the 150) with city/dock water, go back to the boat, and pump it into the tanks. No heavy lifting and you get all the water you want in one trip with no worries about dirty harbors!

If you fill your tanks, use the remainder to wash down the boat.

With that said, we did just get a watermaker because when we were last in the bahamas we learned we appreciated spending long periods being still in places without a fresh water supply conveniently located. Combined with our obsession with fresh water washdowns, equipment cleaning, and multiple showers each day... we are heading back there soon.

^^^^^^
Ding Ding....
Is a water maker a requirement to go cruising? No.
But neither is a lot of equipment commonly found on boats today that want to Go Cruising....Not Camping....

[a64pilot]

I wanted one, cause I like being where others aren’t. One big reason they aren’t there is water isn’t available.
I read where people can make a 100 gls last for weeks. Well we can’t or more honestly don’t want to have to, and I’m not about to ask her to either. We are older now and lazy and enjoy our luxuries.
Not having to be tied to a dock to get water opens up a lot more cruising grounds, we can now go places we couldn’t and or stay places longer and maybe not have to leave when weather isn’t all that good, because water supplies are getting low. Food and fuel are our limiting factors now, so the time we can spend away from civilization just got increased by an order of magnitude.
Now I just need to find a way to get unlimited wind and fuel

[micah719]

Go nuclear!

[MV Wanderlust]

Originally Posted by a64pilot

I wanted one, cause I like being where others aren’t. One big reason they aren’t there is water isn’t available.
I read where people can make a 100 gls last for weeks. Well we can’t or more honestly don’t want to have to, and I’m not about to ask her to either. We are older now and lazy and enjoy our luxuries.
Not having to be tied to a dock to get water opens up a lot more cruising grounds, we can now go places we couldn’t and or stay places longer and maybe not have to leave when weather isn’t all that good, because water supplies are getting low. Food and fuel are our limiting factors now, so the time we can spend away from civilization just got increased by an order of magnitude.
Now I just need to find a way to get unlimited wind and fuel

That’s our justification and philosophy on having a water maker, too. Stay out longer in places others don’t go.

[a64pilot]

Originally Posted by micah719

Go nuclear!

Yeah I was going to say putting a Watermaker on a cruising boat was sort of similar to Nuk on a sub, but thought it a little silly

[micah719]

In a way, as sailors we already are nuclear-powered; thankfully the reactor is 92 million miles away.

It's getting close, though. How much more complexity can a boat handle and still be reasonably fixable? There must be a point where there are so many systems and parts that the probability of a truly joy-killing failure is so high that one dreads going far away from the supply chain at all; and perhaps considers "getting back to it all" might be preferable to taking it all with you.

Just out of interest, what are your plans B and C, once you're in that ultra remote location, and your watermaker dies? I'm not being contentious, just curious. It's been an informative thread, and the intricacies of enjoying a watermaker make me think they're a nice luxury one should be wary of totally trusting.

[a64pilot]

You always have enough water to get back to civilization or at least to a water supply, then also have a plan on how to capture rain.
I have a furling boom, it looks like a huge rain gutter which it is, it is at a 2.5 degree or so angle to the mast, at the base I have opened up the drain hole and installed a nylon male hose end so that I can easily connect a hose.
You would be surprised at how much rain comes down the mainsail into this gutter of a boom and of course into the water tank if you connect a hose.

I suppose the most conservative thing would be a second watermaker, but do to costs if nothing else I will have to do with just a few spares and a way to catch rain.

I figure two gls of water per person, per day min. You may can go below that, but I’d rather Plan high than low.