Friday, January 28, 2022


RV water: How fresh is “fresh” water?

By Russ and Tiña De Maris

Having your RV sitting in the driveway, “ready to roll” on a spur-of-the-moment trip, is one of the gifts of our lifestyle.

Got propane and gas in the tanks? Holding tanks empty? If you keep a few clothes in the rig, some non-perishable food items, and grab whatever else from your house fridge, your RV is up to an “instant getaway.” Ah, but what about the fresh water tank? How long can you safely keep water in it before worrying about “bugs”?

Our “germ free” society seems to be bent on scaring us to death. If you believe the TV commercials, if you don’t wash with “antibacterial soap” you’re sure enough going to drop over dead. It’s no wonder that many RVers (not just new ones) worry about how long it’s safe to keep water on board. Some even think they should drain their water heater between outings.

We checked with Uncle Sam’s water storage safety experts on the subject of storing “home prepared” drinking water, and here’s the thinking of the Federal Emergency Management Agency (FEMA).

Much depends on the quality of your water source. If you’re filling up your RV tanks with water from a “known” good source (a municipal water supply, as an example) then stop worrying about the water. Before you fill, make sure your tanks are properly sanitized. Not sure how? Check out our post on this subject.

Using a drinking water-safe hose, fill your tank from your safe water supply. Make sure the tank is securely capped to keep out unwelcome pests and road dust. Now settle back and relax. According to FEMA, “Replace the water every six months,” is all that’s required. What about water in your water heater tank? Remember, when you fire up the heater, a lot of bugs are likely to be cooked to death. And if the water supply you originally filled up with is good, then the same “six month” recommendation applies.

If you’re really worried about water quality, FEMA suggests you purchase commercially produced drinking water, and keep it closed until you need it. It should be good until the “use by” expiration date printed on the bottle.

##RVT829 ##RVDT1408


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Gary Sain
1 year ago

Hmmm. I wish you’d included the link to FEMA on water storage in the article, but I’d like to offer a few comments based on 40 years in the water treatment business drinking water and high purity.
I would not recommend leaving water sitting stagnant in your freshwater tank for 6 months. Even if you’ve disinfected your system and you put chlorinated water in the tank, there’s some things to take into consideration. As noted, water systems should be sanitized and the chlorinated water is disinfected. However it is not a sterile system. There’s a difference between the two. We treat our systems and drinking water to remove pathogenic (disease causing) organisms but they are not bacteria free-sterile. So while I wouldn’t be particularly concerned from a disease standpoint with leaving water in a tank for extended periods, you could be sitting yourself up for bacterial, particularly slime growth. If it gets bad enough, you can start fouling lines. (con’t).

Gary Sain
1 year ago
Reply to  Gary Sain

Slime is very hard to remove once its there, and bacteria in the slime won’t be killed when you next disinfect your system. Disinfection doesn’t really remove it either once its established. In short, slime’s not a good thing to have. You noted that to store water, the container needed to be closed. FW tanks are vented, and they do ‘breathe’ as temperature varies and air is drawn in and out. Incoming air brings in dust, microbes etc and the chlorine in the water will be gone in a day or two. I personally wouldn’t leave water sitting in my tank for over a week or so, if I wasn’t using it and regularly adding fresh chlorinated water. On the hot water tank I’m not so worried, since I’m not drinking it. I leave it alone during camping season, but drain it for the offseason. The heating cycle does control general bacterial growth. However, there are some bacteria that are fine with the hot water-they’re the ones that can cause the rotten egg smell in shower. Then its time to disinfect.

M. Will
1 year ago

I only drink water out of my water tank in my TT. Any water that I put into that tank I filter it while its going in. I do not use any campground water that comes out of a tap. You have no idea about the quality of that water. The water in the tank that is used and filled and refilled regularly is constantly being cycled and doesn’t sit around in the tank going bad. I have never had any problems. I also believe that if you really think that the $20 Camco blue water filter is saving you from any bad water issues then you are very naive!!

Sink Jaxon
1 year ago

I now use a Berkey water filter. Goes from my fresh water tank to the Berkey for cooking/drinking/coffee. I’m really working on using less plastics, considering how much the oceans and marine life are being affected by plastic. A Berkey is expensive outlay but lasts a long time. Will filter up to 6000 gallons of tap water. That of course is a baseline. It will filter water from a lake safely, but of course the dirtier the water the shorter the filters will last.

Robert Pulliam
4 years ago

We spend the winters in FL and most of Florida has sulfur taste to their water which we find unpleasant, we carry a number of empty gallon jugs with us and fill them at the purified water refill station in the local Walmart or other store where we are staying. It ranges from $.27-.33/gal. Is tasteless and purified and cheaper than bottled water and we are reusing our containers and not adding plastic bottles to the local dump.

4 years ago

Never feeling comfortable drinking water from my fresh water tank, I easily installed a separate water system and pump it out of the 5 gallon plastic jugs to a dedicated drinking faucet in my RV kitchen. While wintering in AZ I can buy 5 gallons of good water for 50 cents. I alternate between two jugs so I always have water at the ready.

4 years ago

The reason I empty the water heater tank is not because I’m afraid the water will go ‘bad’, it’s because I want to get a little more mileage out of my sacrificial anode rod.

4 years ago

Putting on my professional hat again, this article and comments so far nail it. Water in your tank is completely safe after 6 months if it was safe after 6 minutes. Municipal water is treated to last conservatively that long in a tank (and in fact, FEMA says at least *2 years* for home-bottled water in closed containers).

Generally, assuming your water was safe to start, DO NOT worry about bacterial growth. You’ll use the 40gallons of water in the RV long before 6 months is up or else need to winterize before then — either way, it’s dumped/sterilized before an issue.

Tommy Molnar
4 years ago

I don’t understand the worry over water in the “fresh water” tank. If you drink the water out of your faucet at home, and you put THAT water into your fresh water tank, I think you’re good to go. Down the road, if you drink the water at campgrounds (state or private), then you should be fine putting it into your fresh water tank. We add the commercially available ‘fresh water chemical’ to our tanks, then for drinking, run it through our Brita filter. So in over 20 years of RV’ing, neither me nor my wife have gotten sick or died . . . .

Bob Godfrey
4 years ago

What most folks fail to realize is that a large portion of bottled water supplies are from municipal facilities. Excellent marketing has convinced many that bottled water is the only water you can safely drink and that is far from the truth. I had a friend who’s father owned a beer distributership in Texas and he made more money selling bottled water than he did beer. It’s a fad and actually detrimental to the environment since so many plastic bottles are thrown away with water still in them, never to return to the earth until the plastic disintegrates which could be hundreds of years.
Less worry……..more living!!!!!

William Fouste
4 years ago
Reply to  Bob Godfrey

I prefer the “Purified Municipal” bottled water as I dislike the minerals in “Spring Water”. Water for carbonated beverages/bottled water is also filtered with reverse osmosis to remove minerals and chemicals.

A good restaurant will serve you filtered water from the beverage machine, not from the faucet.

John Tasselmyer
4 years ago

A teaspoon of bleach in a stored water hose helps keep things fresh. I always store my hose with ends attached.
If you have dead leg water lines, like an uninstalled washer option, be sure to open and sanitize these lines occasionally. Neglecting this step can cause smelly water from the nearest sink.

Jay French
4 years ago

Personally, I never drink “Campground” water or water from my fresh water tanks. This is used for showers, toilets & sinks.
But I have never kept water in the tank for longer than 1 month. Just as I use a portable dump station every 2 or 3 days regardless of total accumulation.

François Rochon
4 years ago

What is water.. I often say… it’s dinosaur pee !! Water on this planet has been here for millions of years and regularly recycled , Bottled water should be good indefinite time, the “best before” date is just a way that companies make sure you will buy more…
Yogurt is good at least two months after the date, so is cheese. Canned food as long as the can is in good shape and not rusted, eggs for at least a month after the date and so on !

Bob Packer
1 year ago

Only thing I don’t eat or drink long after the “expiration date” are tomato products, But, even then, I use them up to a year past the label on the can.

1 year ago
Reply to  Bob Packer

I’ve had tomato puree eat through the inside lining in the can after several years. So I stopped buying 12 at a time at Costco.