SailNet Community banner
  • SailNet is a forum community dedicated to Sailing enthusiasts. Come join the discussion about sailing, modifications, classifieds, troubleshooting, repairs, reviews, maintenance, and more!

Drinking water tank water.

14K views 88 replies 44 participants last post by  mark2gmtrans 
#1 ·
My boat carries 2 water tanks, 50 and 30. The water in them is regularly used. I average going through one tank a month and so the water is constantly being replaced. But, we never drink it or cook with it. We always buy bottle water.

The other day I say a product that 'freshen' or removes order, or funny tastes.

I was wondering, how many actually drink the water in their tanks?

I would like to stop buying bottled water. And just use the water from the dock water supply.

I guess I just assume the water lines at the house are clean enough to drink from but wondering if the water systems on an average boat would be just as clean.

I do run bleach through the system every now and again.
 
#3 ·
I never drink water from my 75-gallon tank. For drinking purposes, I use bottled water. I do, however, use the water to wash dishes and shower. However, before doing so, I make sure it is well chlorinated. I add a full cup of bleach to the tank when I fill it, and while this is far more than necessary to sterilize the water, I just feel better about it. There is a recommended formula for water sterilization, which if I recall correctly is 8 to 16 drops per gallon. And, if you cannot smell the chlorine when running water from the tap, there's a good chance that there is not a sufficient amount in the water to make it sterile.

My boat has been sitting for a couple weeks, therefore, next week, I'll completely drain and flush the entire freshwater system, then after refilling, hit it with an extra load of chlorine, flush it through the system until the tank is half empty, then fill it to capacity. This should make the water safe enough for pretty much everything when I make that next 3-day cruise down the bay.

Good Luck,

Gary :cool:
 
#4 ·
Wow.
Different strokes for different folks indeed.
Not only do I drink from my tanks, there have been times I was overjoyed to be able to fill them from a primitively built, unfiltered catchment system.
In the Bahamas we figure if there are frogs swimming around in your catchment tank, then the water is not poisonous so it's good enough to drink.
Be that as it may, I bet my immune system is better than all you cautious bottled water drinkers.
 
#5 ·
I regularly use the water tanks onboard for drinking, washing cooking, etc. Regular use, regular cleaning, and I fill from municipal supply. I do use a charcoal filter on the tap for drinking to make it taste good. Very few bugs are resistant to chlorine, and those would be make the evening news if they were coming from a municipal supply. Residual chlorine = safe water. Can check residual chlorine with a simple paper strip if concerned.
 
#8 ·
Not a significant threat when using a municipal system to fill tanks, there is a greater risk of giardia contact when swimming n the marina pool.

There are several bugs that are not killed by chlorination, but again, I don't consider them a viable threat if filling from a municipal source. Streams, cisterns, ponds, long stagnated sources, are a different story.

No wrong answer here though. Everyone should do what they are comfortable with.
 
#7 ·
When we refill our tanks (110 gallons) we run the source water through a 10 Micron filter canister and add 2 Oz of unscented bleach to each tank. The following day we add AquaBon water treatment to each tank. Water from the tanks is drawn through a 2 micron activated charcoal filter (Pentek). The water that is used for drinking, making GatorAid, etc. is run through a final, under counter, SeaGull filter and has no unpleasant taste or scent. We clean and flush the entire system annually and replace the filter cartridges and have been very pleased with the results for 10+ years.

FWIW...
 
  • Like
Reactions: JimMcGee
#9 ·
I fill my main tanks through an omnifilter whole house filter that I have modified so that I can attach a garden hose. I also treat the tanks with bleach at each fill up. The water in my main tanks taste good, better than some municipal water ive had. But I don't drink from the main tanks typically.

For drinking water I have two 5 gallon food grade jugs that are mounted in the lazarette. They are easily removable for thorough cleaning or replacement if they get funky. I can fill those with bottled water or from the omnifilter.

I have a separate pump/faucet at the galley sink for those tanks. A hand operated pump for drinking water, a foot pump for wash water.
 
#10 ·
We drink from our water tanks. What we have done is open up the inspection ports and clean them with bleach. The water at the harbor is chlorinated city water so I'm not really concerned about sickness. For drinking we have a Pur filter pitcher that we use to take the smell/taste out of the water with -- that being said I often just drink from the tap with no ill effect.
 
#12 ·
I bought my boat with unknown water in the tank. I've since used half and filled and use half that and filled. What can I do to clean it and start using it to drink? Taste doesn't bother me. I've been thinking about this. I don't have a good way to empty it. It has a hand pump sink and probably would take hours to pump it all empty. Just out some bleach in and call it good?
 
#30 ·
It has a hand pump sink and probably would take hours to pump it all empty.
My Catalina 25 had a hand pump and it took about 10-15 minutes to hand pump the 20 gallon tank dry.

I took that tank home, added an inspection plate, carefully cleaned it, and replaced all lines. We drank the water from it with no concerns.

I didn't take my Pearson apart to remove the water tank, I just cleaned the system and drink the water and it's also been fine.

I hate bottled water, what a waste of storage space (the dead space between bottles wastes a lot) and resources.
 
#13 ·
You should have an access plate (if you dont consider adding one).

I empty the tanks in the winter. To empty the tank i use a small rule pump. I wired in a cigarette lighter adapter to power it. And i have a length of hose connected to the discharge. I drop the pump in the tank,plug it in, and let it empty the tank. I use a sponge to scrub and get the last of the water.
 
#14 ·
Even municipal water systems kill people.
Why would anyone even chance it. Without bottled water, using your water tank as your only source of water is risky at best.
I can just imagine what it would be like to have 4-5 people on board, 3 days out, and you all have violent diarrhia with no water to drink.
Now there is some good planning.
 
#15 ·
Yes, I drink, cook, shower with my water tank supply. I get my water from a safe shore supply. But here are a few things that I have done or currently do to ensure my water is safe.

Water tank treatment (Peggy Hill)

Turn water heater off at the breaker before beginning. Do not turn it on again until entire recommissioning is complete.
1. Prepare a chlorine solution using one gallon of water and 1/2 cup Clorox or Purex household bleach (5% sodium Hypochlorine solution ). With tank empty, pour chlorine solution into tank. Use one gallon of solution for each 5 gallons of tank capacity, which results in 4 Ounces of bleach for 10 gallons of water.
2. Complete filling of tank with fresh water. Turn on every faucet and allow water to run until what's coming out smells strongly of bleach.
3. Turn off faucets--but do NOT turn off the pump...it must remain on to keep the system pressurized so that the solution remains in the lines. Allow to stand for at least 3 hours, but no longer than 24 hours.
4. Drain the tank through every faucet.
5. Refill tank with clean fresh water and drain again through every faucet.
6. To remove excess chlorine taste or odor which might remain, prepare a solution of one quart white vinegar to five gallons water and allow this solution to agitate in tank for several days by vehicle motion (iow, go sailing and tack a lot).
7. Drain tank again through every faucet, and refill with potable water.

Beneteau Horizons

How to Purify Water amount of bleach per gallon
 
#16 · (Edited)
For my tanks, (30 gallons) this would mean that I would be pouring 3 cups of bleach and 1 1/2 gallons of vinegar into the ocean.
We use a small chlorine puck to make the water safely useful, but we still show concern for our environment.
If we do need to use some of the water for washing, doing dishes, etc, we will boil it, but even boiled we still don't drink it.
 
#17 ·
Mike, you must be the luckiest guy on the planet. Especially if you drink water from a source that you believe is safe because you've seen frogs swimming around in it. Keep in mind that those frogs eat many of the other insects and insect larvae that also survive in those waters, critters that can eat holes in your intestines and take up refuge in other body parts. There are loads of parasites in those ponds. Now, I have to admit it has been a long time since I was in the Bahamas, but if I recall, the municipal water supplies there were not all that safe. Yeah, you might get away with drinking tapwater, but that doesn't mean your immune system is any better than anyone elses - it just means you've been quite fortunate.

As for bacteria resistant to chlorine, I don't know of any. In fact, good old Clorox Bleach, especially in heavier concentrations, kills all living cells. It doesn't discriminate. When I was a young man and working for University of Maryland Hospital, one of the projects we were researching was trying to find a new antibiotic that would be effective on TB. We would pipette live TB into Petri dishes, then add tiny tabs coated with various, new antibiotics to see which ones killed this very virulent strain of TB. We wore full body, disposable coveralls, full face mask, gloves, booties, etc... - that virus was really nasty.

Our pipets were precision, glass tubes that accurately measured microscopic amounts of the virus in solution. They cost a bundle, and normally, they were washed, then steam sterilized. About half of them usually ended up broken just from the sterilization process. I made the big mistake of adding a capfull of Clorox Bleach to the washer, which was less than an ounce. The pipet washer ran all night long, probably a couple hundred gallons of water went through them, then then next day they were steam sterilized and dried for use.

We thought we had discovered the miracle antibiotic - one that killed the TB instantly. Each day, when we pipetted the TB into the petri dishes it died - instantly. After a week, we got a new shipment of pipets in the lab, went to work, and damned if the TB didn't grow just like it always did. It didn't take long to narrow down the reason the virus died. It was the residual chlorine in the pipets.

Now, if anyone out there knows of any form of bacteria that is resistant to chlorine, please feel free to post the information. I, for one, would really like to know about it.

Cheers,

Gary :cool:
 
#56 ·
Now, I have to admit it has been a long time since I was in the Bahamas, but if I recall, the municipal water supplies there were not all that safe.
Actually, many of the supplies in the Bahamas are now from RO, so they're pretty safe...

Frankly, I'm amazed at some of the replies in this thread... I'm with the crowd that has been using my tank water for everything for years, refreshing it frequently, of course... I built large access ports into my tankage, it's pathetic the lack of attention many builders give today to the importance of being able to keep your tanks clean...

Always carry an emergency supply in bottles, of course, but I'm with those who are appalled at the massively wasteful, unnecessary, and destructive impact of the bottled water industry on the environment... I would hope we as sailors would be doing our utmost to help minimize that sort of impact, it's not all that difficult to configure a safe system aboard any boat today...

Every true voyaging boat should have a means of catching rainwater IMHO, amazing what a good tropical downpour can produce in a matter of minutes... Anyway, I'm glad to see I'm not the only one here who apparently is of the opinion that our - particularly my American brethren's - paranoia over this matter, and our increasing dependence on bottled water and onboard watermakers, has gone just a bit over the top... (grin)
 
#19 ·
Gary,
When I said there were several "bugs" resistant to chlorine I was referring to protozoa and viruses, not bacteria. Particularly giardia, cryptosporidium, entomoeba, and the likes. They are highly chlorine tolerant but also nearly non-existant in municipal water supplies.

Significantly greater threat from surface water sources, even swimming pools.

Dog Ship- a quick Pub Med search shows 79 deaths related to drinking water in the US from 1971-2004. Not perfect but not bad for a population of 200-300M imho.

Any system aboard that is required to maintain life should have redundancy if you are going offshore. Again, only my own opinion. More than one pump, more than one fire extinguisher, more than a single flare, more than one can of beans, :cool: point is I take more than one water source. I carry bottled water as well when off shore.
 
#20 ·
We do carry some bottled water, and will drink that if we're drinking a glass with a meal, for example, but we use our tank water for coffee, tea and other hot beverages as well as washing up, of course.

We use a Brita faucet filter, and everything we drink goes through that. Since the filter is selectable, we don't waste filter life on wash water and water not intended for consumption.

There's no filter in the head so we use tank water directly for brushing teeth with no ill effect to date...
 
  • Like
Reactions: smackdaddy
#21 ·
Yes Silvio, the numbers are extremely low because by the time people start to die we have long since found the source of the problem.
It doesn't tell you how many people fell ill.
 
#24 ·
I only "liked" Mike's post out of shear sarcasm. The rules for safe drinking water have been known for a long time, they don't require bottles, and cruisers can't fill them at home anyhow... obviously.

"Ew" is tired.
 
#25 ·
Cruising; I would think most don't consider cruising a wilderness survival trip and do plan to make landfall every few days or week. Weeks alone at sea, of course is a whole different plan on self sufficiency. Ewwwwwwwwwwwwww is and will always be my reaction to tank water for drinking. Taste is my reason more then safety. EW!
 
#26 ·
We have household-style charcoal 3M cartridge filters between our tanks and the faucets (even our foot pump). That gets rid of 99.99% of all bacteria and contaminates which is as good or better than most water supplies. I change those cartridges once a season. I typically drink bottled drinks on the boat ... but I am comfortable washing hands, dishes, brushing teeth, showering etc. with this water. I would certainly drink it if that was all we had. But why drink water, when there is beer. That's silly.
 
#27 ·
I am in my 11th yer as a full time liveaboard. We always always drink from our tanks. Never used bleach or any other additive.

I am a little bit careful of water from an island like Carriacou where the water is collected from roofs and stored in home cisterns then pumped out and sold to yotties. That I boil before drinking.
 
#29 · (Edited)
People think that bottled water is "purer" than what comes out of their faucets at home. This may not be the case. Companies that bottle water sell the idea that they have a spring in the mountains (or out in the woods, or somewhere green and pretty) so their water is better. If you believe them, they make money. I think Coca Cola puts Philadelphia city water into blue bottles, calls it something fancy, and sells it nationwide at an incredible profit. Is it any better than what might be in your tank? The Royal Navy used a fresh water source that welled up in one section of Cold Spring Harbor, New York, to fill their water barrels before and during the American Revolution. Now a faucet has been set up that taps into this same source, so that you can actually sail up to it, (about 100' from shore) and fill your tanks too. The Royal Navy would not want their crews to get sick, any more than any of us do. I absolutely hate the plastic bottles. When they're full, they're heavy. When they're empty they roll or blow around everywhere, causing crew to dangerously miss their step when they crunch or slide underfoot. If there is an "Ew" factor, clean your tank. and consider the drinking water on Bermuda. EVERY HOUSE in Bermuda funnels rainwater from the roof into a cistern that is probably NOT as pristine as your boat's water tank. There might in fact be frogs down there.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top