How long is it safe to leave fresh water in the tank and system between trips?

Wayne

Administrator
Staff member
I've often wondered how long it is safe to let fresh water sit in the tank and system between trips. We almost always fill with city water that is treated. How long can treated water sit in the tank and system before biologics will start growing or will they?

The longest we have left fresh water sit in the tank and lines between uses is a couple months. The next time we get the trailer out for a trip, we always flush the fresh water tank, then fill it with treated city water. Then we flush the kitchen sink lines by letting the faucet run for a couple minutes. We have our Clearsource dual filter permanently mounted in the basement and always remove the filters so they can dry between trips.

Doing this routine we have never had any smell, taste, or bad effects from leaving water in the system.

What is your time limit for letting fresh water sit in your system?
 
More than a month, and i re-chlorinate. I don't know if a rule of thumb for this. Sometimes i leave the chlorine water in the fresh water tank, and sent it back through the lines, as long as i smell chlorine in the water coming out of the tap.
 
How much chlorine do you use?


Which leads to another question, is it better to have the tanks drained and dry vs. leaving water with chlorine added in the tank?
For a 24 hr or longer treatment, I use 1/4 cup per 15 gallons.

For a quick sanitize double it. 1/2 cup per 15 gallons.

Dry vs wet? No data but I worry that with the large volume of air and minimal chorinated water after draining, that the chlorine would gas out and leave dampness that could mold.
 
I haven't given it a ton of thought. We usually travel with about 20 gallons in the tank, just enough for some flushes and hand washing if needed. It stays in at the end of the trip, then before the next trip I'll use that water to put some in the Grey and Black tanks, drain the rest, rinse a little, and refill.

We're doing about one trip a month. I probably ought to just bite it and re-sanitize before the trips. Being as I just got over a nasty stomach thing that put me in the emergency room for the afternoon.
 
I use around a cup for my 40 gallon tank.
Do you pump the chlorine through all of the plumbing, then drain the tank and refill with fresh right away or leave the chlorinated water in the tank and system for a ride to the next campground? How long can you taste/smell the chlorine?

I'm going to have to do this in the spring and an interested in hearing your methodology.

[edit] I didn't see your post above.
 
Do you pump the chlorine through all of the plumbing, then drain the tank and refill with fresh right away or leave the chlorinated water in the tank and system for a ride to the next campground? How long can you taste/smell the chlorine?

I'm going to have to do this in the spring and an interested in hearing your methodology.

[edit] I didn't see your post above.
I have a 40 gallon tank, i use about 3/4 cup to 1 cup of bleach( regular bleach not the non splash formula). I run the pump and start furthest back, which is my bathroom, i run it through the hot water side first then the cold side. I do this at each point until i smell the chlorine in the water. Toilet and outside faucet. That way every pipe has been sanitized and wont re infect the system when the chlorine is gone.

I generally do this if the trailer sits more than 2 weeks between trips. I don't use the fresh water tank much, so i leave the chlorine in, and its good for a month or two. That way i don't have to mix more, i just run the pump when i'm not connected to a water tap.

After 24 hours, i drain the water heater, and open the low point drains. Run some water through the hot side at the campsite so the first shower is not overly chlorinated.

Probably overkill, but i don't want giardia!
 
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I have a 40 gallon tank, i use about 3/4 cup to 1 cup of bleach( regular bleach not the non splash formula). I run the pump and start furthest back, which is my bathroom, i run it through the hot water side first then the cold side. I do this at each point until i smell the chlorine in the water. Toilet and outside faucet. That way every pipe has been sanitized and wont re infect the system when the chlorine is gone.

I generally do this if the trailer sites more than 2 weeks between trips. I don't use the fresh water tank much, so i leave the chlorine in, and its good for a month or two. That way i don't have to mix more, i just run the pump when i'm not connected to a water tap.

After 24 hours, i drain the water heater, and open the low point drains. Run some water through the hot side at the campsite so the first shower is not overly chlorinated.

Probably overkill, but i don't want giardia!
I think I'm probably going to adopt something like that. I really don't give a lot of thought to the freshwater tank since we don't boondock and really all we use it for is flushing and washing hands when we're on the road. I should probably be a bit more careful. Especially since our climate means that the tank is probably always warm and steamy, good place for nasties to grow.
 
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