Drinking water from your tank

I am a total convert to the General Ecology filters. Firstly you don't have to worry about e-coli, secondly the filters remove all taste so if you are in the Balearics it won't matter and lastly you don't have to lug and store plastic bottle of water.

http://www.purewateronline.co.uk

I don't think any of the other filters sold by chandlers will remove e-coli or taint.
 
blxm said:
Interesting that in all the posts nobody has said that they have got sick from drinking water from the tank.
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I think I have. When viewing the boat I ended up buying, I also took a sip from the tap, as funny taste can tell of plumbing issues. Tasted fine to me. A day later I came down with a strange flu - intense but shorter than usual. Didn't think anything of it, sitting/standing on various crowded trains for six hours there and six back I had plenty of opportunity to catch a virus.

Hired a surveyor who came to the boat about two weeks later. I wasn't there at the time, and his report was late, so I rang him and he told me he had some weird kind of flu. Didn't realize until much later when I researched water tank treatment what the likely cause must've been: Pontiac Fever, the other (and less harmful) disease caused by the Legionella bacteria, which has exactly the above mentioned symptoms and would be prevalent in a tank that had sat untouched for years - and by then I had learnt that was the case with this boat. The surveyor had taken a sip from the tap too.

After the purchase went through, I opened up the inspection hatch, found some minor dirt which I cleaned out, and then "shocked" the tank, pipes, taps, etc. with a strong bleach solution (pretty much as described in jimbsail's useful link), flushed a couple times and refilled. Myself and others have been drinking from the tap ever since, with no further issues.

When I refill the tank, I have some watery bleach in a spray bottle with which I spray on the outside of the filler before opening it, as well as on the marina hose. I run the hose for a little while before putting it in the tank, for useful purposes such as cleaning the boat. Then I drop in a very light dose of sodium dichloroisocyanurate (100 tablets £2.56 - same as Milton, minus the brand tax).

I have a TDS meter from a previous hobby, which shows the same TDS of just under 300 ppm for my tank water that it shows on tap water in the flats* next to the marina. Occasionally I check this, mostly as demonstration while "I'm not drinking from your tank, EWWWW" people are visiting the boat.

* Actually the flat had a problem with something leaching in from the pipes and you had to run the tap for 1-2 minutes before the water stopped tasting funny and dropped below 300 ppm. Funnily enough, most people would happily drink that.
 
Yngmar said:
... I have a TDS meter from a previous hobby, which shows the same TDS of just under 300 ppm for my tank water that it shows on tap water in the flats* next to the marina. Occasionally I check this, mostly as demonstration while "I'm not drinking from your tank, EWWWW" people are visiting the boat.

* Actually the flat had a problem with something leaching in from the pipes and you had to run the tap for 1-2 minutes before the water stopped tasting funny and dropped below 300 ppm. Funnily enough, most people would happily drink that.
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If you mean Total Dissolved Solids (a conductivity meter) it's essentially useless IMO for checking drinking water quality, as the nature and concentration of any chemical changes from leaching that might be of health concern would be very unlikely to show up in TDS. And changes in bacteria would not show up either, of course. If you wanted some sort of meaningful test, I think measuring chlorine residual would be much more to the point.
 
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When I lived on Nauru Island we used to get water freighted in by phosphate ships on the return journey. Each shipment was tested by the pharmacist at the hospital to ensure the water was safe to drink and on a number of occasions the water was rejected. I really don't think a filter could have made the water safe to drink.

Has someone mentioned these?
"Water purification tablets clean oxide available in 4g or 20g tablets 8 x 4g soluble chlorine dioxide tablets. We recommend 1 tablet per 100 liters for the initial ..."
 
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PET bottles potential health hazard

Wednesday, 29 April 2009 Emily Sohn
Discovery News
Plastic bottles

It's too soon to say whether drinking out of PET plastic bottles is harmful to human health, says one researcher

Water bottles made from PET plastic leach compounds that mimic the hormone oestrogen raising questions about their safety, say German researchers.

Previous research has focused on plastics containing the chemical bisphenol-a (BPA). During that time regular PET plastic water bottles have maintained a reputation as safe, at least as far as human health is concerned.

But new evidence suggests that PET, or polyethylene terephthalate, may not be so benign after all."

I guess the jury is still out.
http://www.abc.net.au/science/articles/2009/04/29/2555698.htm
 
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Cancer Research UK also has comments on this and it's a lot more recent than 2009. You're probably at more risk swimming in water where purified sewage has been discharged with all the oestrogen from female urine...
 
A friend of mine was working in Saudi in the 70s at a remote camp. A tanker came once a week to deliver water. It wasn't until some time later that he found out that the tanker also emptied the cess pit and took the contents back on the return trip.
I've never had a problem with tank water, mine were integral with the hull. I shocked it with high dose chlorination tablets most years and then just used tap water which contains residual levels of chlorine. The water was consumed mostly in the form of tea but occasionally neat. We have a degree of tolerance to contamination. A carbon filter would have got rid of any mustiness.
I inspected the tanks once and found them completely clean apart from a few black specks which I can't identify. Water stored in the dark doesn't grow any bacteria or algae.
 
MagicalArmchair said:
I changed all my knarly 1970s water pipes, tap etc. over winter and scrubbed out the fresh water tank (that was already very clean to my surprise). We have a Whale Aqua Source Clear Water Filter fitted just below the tap:

http://www.piratescave.co.uk/whale-aqua-source-clear-water-filter-12mm.ir

My most awesome crew and first mate (the wife) insists on bottled water, which is just a huge waste (apart from as a backup of course). We always run the hose for a while before filling the tank to make sure we get none of the nice green sludge that grows in the pipes in this nice hot weather we are having. Considering we have some of the best drinking water in the world, is there any reason she should be shy of drinking water from the tanks on board? Does anyone add anything else to their water tanks, purification tablets, err, or something?
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The Head Mistress, who used to post here always recommended that you did preventative cleaning on a tank and water system.

So I pour in 2 mugs of thin bleach and fill my tanks about a 1/4 full or less. I then run the taps through and then them off and leave the bleach solution in the pipe for 12 hours. I then pump all the water out and refill tanks.

The water will smell of chlorine for the first 2 fills, getting much less second time round, but it cleans the whole tank. I do this once a year.

Mid season, I will add 1/4 cup - that will smell but you can still use it for washing, kettle and drinking as the chlorine will evaporate off very quickly in the air if a jug of water is left to stand. Her indoors doesn't like the smell......... but it soon goes and the concentration is so small as to be harmless.

The result is that the tanks (and pipes) are very clean.

Edit: Do I drink the water - I am happy to do so, but we normally drink chilled bottles from the fridge. Med water is mostly potable but can be salty - but that makes excellent coffee!
 
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Chris_Robb said:
The Head Mistress, who used to post here always recommended that you did preventative cleaning on a tank and water system.

So I pour in 2 mugs of thin bleach and fill my tanks about a 1/4 full or less. I then run the taps through and then them off and leave the bleach solution in the pipe for 12 hours. I then pump all the water out and refill tanks.

The water will smell of chlorine for the first 2 fills, getting much less second time round, but it cleans the whole tank. I do this once a year.

Mid season, I will add 1/4 cup - that will smell but you can still use it for washing, kettle and drinking as the chlorine will evaporate off very quickly in the air if a jug of water is left to stand. Her indoors doesn't like the smell......... but it soon goes and the concentration is so small as to be harmless.

The result is that the tanks (and pipes) are very clean.

Edit: Do I drink the water - I am happy to do so, but we normally drink chilled bottles from the fridge. Med water is mostly potable but can be salty - but that makes excellent coffee!
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The method she quoted is based on ASNI standard A119.2 section 10.8. , which has been reviewed and accepted by the US Public Health Service.

1. Turn off the hot water heater until finished.
2. Remove any carbon canisters or micron rated filters. Remove any faucet aerator screens. Wire mesh pump protection strainers should stay in place. The plumbing will slough off a layer of bacteria during later flushing steps.
3. Clean and remove the vent screen and flush the vent hose.
4. Use the following methods to determine the amount of common household bleach needed to sanitize the tank.
a. Multiply “gallons of tank capacity” by 0.13; the result is the ounces of bleach needed to sanitize the tank. This is 1/8 cup of plain bleach (no fragrance) per 10 gallons.
b. Multiply “Liters of tank capacity” by 1.0; the result is the milliliters of bleach needed to sanitize the tank.
5. Mix the proper amount of bleach within a 1-gallon container of water. This will provide better mixing and reduce spot corrosion of aluminum tanks.
6. Pour the solution (water/bleach) into the tank and fill the tank with potable water.
7. Allow some solution to escape though the vent, if safe and applicable (some boats use the vent as an over flow, while in some cases the vent is in the interior). This will sanitize the vent line.
8. Open ALL faucets (hot and cold) allowing the water to run until all air is purged and the distinct odor of chlorine is detected. Leave the pressure pump on.
9. The standard solution must have four (4) hours of contact time to disinfect completely. Doubling the solution concentration allows for contact time of one (1) hour.
10. When the contact time is completed, drain the tank. Refill with potable water and purge the plumbing of all sanitizing solution. Repeat until bleach is no longer detectable.
11. If the smell of bleach persists after two refill and drain cycles, add a teaspoon of hydrogen peroxide per 20 gallons and mix. The peroxide will oxidize the hypochlorite to chloride (salt) and oxygen, neutralizing the bleach. Any excess peroxide will be harmless to drink and will have no taste. Peroxides are common ingredients in commercially available water freshening preparations.
12. Replace all filters and the vent screen.
 
ghostlymoron said:
A friend of mine was working in Saudi in the 70s at a remote camp. A tanker came once a week to deliver water. It wasn't until some time later that he found out that the tanker also emptied the cess pit and took the contents back on the return trip.
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Yikes! He's really lucky not to have caught something.

Back in the '80s when I lived aboard my 45' cutter, the liveaboard community at the marina used to run underwater hoses from the shoreside bathhouse to each boat in the winter, with electric heat tape from the waterline to the inlet fitting. Near winter's end, I came down with a nasty case of Hepatitis A. The source was a mystery until we pulled up the hoses in the spring. The hose to my boat had been cut and respliced in mid-channel, likely by a boat that had sucked it up in his prop. Nobody informed me that my supply hose was full of funky marina water, and that was likely the source of my Hep A.
 
We use bottled water for drinking in both our boat & caravan. Even after it's boiled water stored in plastic containers for any length of time tastes poor and plastiky even if the water going in was good to begin with. Just use the onboard tank for washing etc. 3ltr bottles of basic water in supermarkets are very cheap.

It's relatively safe though and a carbon under sink filter helps but easy enough to pick up water when supplying. It's only used for tea & coffee as we normally have flavoured waters/soft drinks or alcohol otherwise.
 
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We always drank water straight fromthe tank. If I had to clean the tank I emptied most of the tank and put in a quarter cup of bleach for each 40 gallons filled the tank then ran the taps to clean the pipes. I left it for 12 hours pumped it out, filled the tank, emptied it and filled it again.
 
We always empty our tanks at the end of the season, then refill in the spring adding 2.5ml of Milton sterilising fluid per 5000ml of water in the tank. The dilution used to be printed on the side of the bottle but is now removed so as to allow larger print for the health and safety label! If you Email Milton (Hayley.Johnston@ceutahealthcare.com) they will confirm it for you and it's suitability as a long term solution to keeping water safe to drink.
HTH
 
thinwater said:
7. Allow some solution to escape though the vent, if safe and applicable (some boats use the vent as an over flow, while in some cases the vent is in the interior). This will sanitize the vent line.
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That's a good point. My vent is in the topsides, and I was concerned about it taking in seawater when heeled, so when I re-did all the plumbing on board I fitted a longer hose that loops up inside the cockpit coaming before coming down to the vent. However, this necessarily involved a horizontal or slightly dipped section of hose, rather than a continuous steep fall to tank on one side and vent on the other. No sign at all of any problems, but I have occasionally wondered about water collecting in that dip, stuff growing in it, and eventually getting back to the tank.

I think next time I clean the tank I will try to block the filler around the hose, hopefully pressurising it enough to force some of the cleaning solution up and over the loop to flush out the vent hose.

Pete
 
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