Adding supports to RV holding tanks
How can I support my RV’s fresh water tank?
Can I drive or tow with water in my RV’s fresh water tank? I see that question a lot and the answer is, “it depends.” While it might be assumed that tanks are intended to hold water while driving, that’s not always the case.
In fact there’s a famous email response from one manufacturer stating that you shouldn’t travel with water in the holding tanks as reported by RVMiles. So what’s the solution?
Holding tank supports being installed at a Rockwood-Flagstaff factory
Know before you go
Something that’s not common knowledge is that RVs are all built very differently.
But there’s also a big difference between travel trailers, fifth wheels and motorhomes in how the various pieces are constructed and that is especially true in how the holding tanks are hung. Yes, hung.
My specialty is understanding travel trailers and it has been very common to simply place the fresh water tank between the two frame rails and call it good. There are some builders who do place a thin metal band under the tanks and then there are some who really go the extra mile and place substantial metal supports under the tanks.
With water weighing in at 8.3 pounds to the gallon you’ve got to think that this adds up pretty quickly. That means that even ten gallons is 83 pounds and 53 gallons, as we have in our own trailer, is almost 440 pounds. Wow.
It used to be easier to tell how the tanks were supported before it became common to enclose the underbelly of trailers but you can also research this. But what if you don’t have reinforcements and want to put them in yourself?
Reinforcing your RV’s fresh water holding tank
There are a lot of ways you can reinforce your RV’s fresh water holding tank including removing the underbelly material, called Chloroplast. This is essentially corrugated plastic that’s much like a plastic cardboard material.
But several RVers in our Facebook Group have come up with a no welding, no muss solution.
These clever RVers have taken a product called Unistruts and then cut them about the width of the chassis frame rails. Then they used strut beam clamps to simply support the Unistruts across the chassis.
The examples I saw all did this outside the Chloroplast as well so it was a relatively simple upgrade.
Another solution - ratchet straps
Our friends at TNT RVing did another solution using ratchet straps. We’ve included their video here.
A funny story
We had our own water tank failure in our first small trailer. Essentially those were the days that the undersides of trailers like ours didn’t have any enclosure so the tank was more exposed to the elements.
Our fresh water tank split open which is also when we discovered missing bolts holding the trailer body in place
We were driving up the 5 Freeway in Northern California coming from the Quartzsite RV Show when I noticed a huge plume of what I thought was steam coming from one side of the trailer. We immediately pulled over and that’s when we discovered that the tank had literally split open and was spewing water along the freeway.
Quite honestly I thought it was a smoking bearing so this situation was a bit of a relief, actually.
It turns out our tank was just lodged between the trailer's frame rails with a single strut across it as support. By this time we had amassed tens of thousands of miles on our little trailer so there had been plenty of bouncing on that fresh water holding tank.
Ultimately I paid our local RV tech to simply replace the tank which was no small task as he had to cut the cross support member and then re-weld it.
In the photo I took on the highway (we take pictures of everything!) notice, also, that one of the bolts holding the trailer body to the chassis was missing. We found out this wasn’t the only one and replaced those bolts with units that had nylon in them so they wouldn’t back out.
What should you do?
First things first, I would learn how your own RV holding tanks are supported. As mentioned, some are pretty well supported, others are not.
Another option might be to travel with only a minimal amount of water in your RV’s holding tanks and use these Wolverine Tough Bottle bags to transport water.
As with so many things, the more you understand your RV and how it’s built the more likely your experience is going to be StressLess Camping.
Our free resources for RVers
