fresh water capacity - brunnhilde part 1

I posted this post a few weeks ago on May 14. However thanks to the stupid autosave "feature" the post was trashed with a very early version. I hate writing the same article twice so grudgingly I am reposting this draft for now, and will refine it when I have time.


I have been mulling over the how to increase the fresh water capacity in Brunnhilde for a long time. I have not disillusion about Westfalia had already done an incredible job in engineered a very well balance water system giving the extremely limited volume in this compact camper.

In my years of use, my experience when I wish I have more fresh water is when I am staying in a city far away from camping facility to replenish water. Also with out modest water capacity, I feel getting the short end of the stick when RVs twice our size with 5 times the water capacity pay the same charge.

Surveying the potential location to carry this extra capacity, my estimate is no more than 20 gallons in addition.

Picking up a 7-gallon water carrying tank reminds me how heavy water is. It is a three dimensional problem as you increase the volume. I saw a lot of tanks offer for sale as RV water tanks. Most have next to no specification except the volume and outer dimensions. I suspect a lot of these are marginally durable if you choose a larger capacities, unless you encapsulate it in a cavity that restrains the side walls from bulging out.

The ones that have higher quality are those sold for marine applications with specificed USCG standards. I found the Todd brand which give the wall thickness. I now remember seeing them at West Marine circa 15 years ago and were impressed by the thickness and heft.

I did some quick measurements at my planned mounting location. I chose the right side of the storage under the wet cell wanting to reduce the left biased weight distribution in the factory configuration.

D = 25 inches
W = 25 inches
H = 13 1/2 inches

this is the heavy duty line with 5/16" to 3/8" wall thickness

this is the standard duty line with 1/4" wall thickness

The pre-made ports on these tanks are pose installation difficulties. Fortunately the company makes a very nice and reasonably fitting relocation kit that includes a access lid which would just be perfect for installation of a submersible pump.

Looking through the lists there are three tanks that are viable. A heavy duty 13 gallon, a standard duty 13 gallon, and a standard duty 15 gallon. That will add about 125 pounds of laden weight slightly behind the rear axle.

Seems there potentially a problem that any one of these three tanks are not viable.  For my installation the height cannot exceed about 11 inch for serviceability for the access port. Seeing the photo depiction that there are strengthening crease lines on some sides which would not be suitable to mount the big round access port. I went to Todd's site and they don't show the same tanks.The with, depth, and height listing convention also looks to be inconsistent from that on West Marine's website.