Water weighs 8 lbs/gal so it is an issue. We travel with about half a tank in case we overnight at someplace like Walmart and we will have some water to shower, bathroom, etc. For drinking, we always have at least 2 of those big clorox bottles full of water.
Anacortes has some of the best quality water in the US, so we always leave home with a full tank. In a 22,000 max weight rig, 650 pounds of water isn't going to make a significant difference in mpg. Of course, on a long trip we'll end up filling someplace, but having the tank full to start out goves us some options.
We've had some pretty rotten-tasting water at some CGs, so we check it carefully before taking any onboard. We use the CG city water direct from the faucets for most things, but for drinikng or cooking, I shut the CG spigot off and use the on-board water.
I'm giving some thought to putting a solenoid valve at the water inlet so I don't have to go outside to turn the spigot off.
Frank Damp, DW - Eileen
'02 Georgetown 325, F53, V-10, bought used in 2010 at 13,000 miles.
Dogs - 2 Labs again, both yellow males, both 9 yrs old and both adopted.
Our fresh water tank is all the way forward (under the couch), 30 gallons and we usually travel with half a tank. If I'm not sure we can easily get more water where we are going I fill two 7 gallon blue Wally World jugs and they go in the back of the truck, under the Leer and all the way forward with the other heavy geer (firewood, beer, ammo, golf clubs etc.).
Since our 22' TT has 1966# of CCC filling the water tank full and bringing the two full jugs is another option for places like Quartzite. I just move the water jugs to the rear of the trailer to balance the increased TW from the full tank. With 30 in the tank, six in the water heater and another 14 in jugs we find 50 gallons will last us a week easily, but then it is just my bride, the pooch and I.
I've only traveled twice with the FW tank empty. Both times we knew water was available at our destination. The last time (earlier this season) it was not a problem at all. BUT, the first time we did it, there was only one spigot at the CG, and it was difficult to reach to fill my tank. I only had about 15' of hose and really needed 25'. I ended up going around the loop backwards to put the fill port on the side closest to the spigot, and barely made work. I now have 15', 25', and 50' water hoses.
Usually we travel with a full tank (20gal) filled up at home.
2004 Toyota Tundra SR5 (V8, 4WD, TP, TRD)
2005 Fleetwod Allegance with axle flip
Honeywell 2000i Generator
Me, DW, DS, DD, Dog & Camping Kitty
It depends on the type of trip, but we never travel totally empty, even if we are just going 30 minutes down the road, just in case we need to stop for a bathroom break. I do prefer to bring our own FW since I know the quality of the clorinated city water we fill our tanks with, but if we have been to a specific campground that we know has decent water, we will carry enough for the ride and fill/use what's available at our destination.
When doing short sessions of boondocking, I intersperse into my travel plan stops at RV parks or campgrounds with facilities to take care of waste dumps and fresh water fills. Refueling stops are sometimes water fill possibilities, but you had better ask, because there are places where it has to be trucked in and is almost as precious as motor fuel.
If boondocking close to home, I fill at home. But then I wouldn't be in the category "don't travel with the FW tank full." You gotta travel some distance with it full, if you are headed into the boonies.
I travel sometimes in areas where water is often not available in campgrounds, and other times through places where it is readily available and they don't mind you taking away 50 or 100 gallons for the price of an overnight stay, or as a courtesy with a gas fill-up.