H'mm, we all seem to come at boondocking and save water in different ways. All are good, and I did pick up a few tips I had not thought about. One is, collecting the hot water line cold water purged in the shower into a container to later use for rinsing in the shower. I will try that one, as it will help our situation.
A few comments to add that may not have been stated.
When the Oxygenics shower head came out, they only offered one style head; now they have many, and I can tell by the number of nozzles the flow rates are different between the models. I have one of the originals; I will have to measure the flow rate. Depending on your water pump's pressure, the shower head flow rate will change. I upgraded to a variable-speed pump long ago; I can get steady flow with steadier lower pressure than the standard on/off pump at 45 to 50 psi.
I added a positive shutoff on the sprayer hose at the shower faucet. The shower head type always seems to drip, cold water, too, it seems. This positive shut-off solved the drip and the constant cold slug issue with shower faucet shut-offs. Yes, we Navy shower also. This positive shut helped save some lost water, the drips, and the cold slug re-purge.
We have a 42-gallon freshwater "system". The amount of water in the fresh tank is about 34 gallons. 6-gallon water heater, 2 gallons in the whole camper piping; once the pump dry locks and sucks air, you cannot use the other 8 gallons held in the system or what is left in the fresh tank. As per the OEM setup, you can never use 34 gallons before the pump lost prime.
I reworked our fresh tank pump suction piping. From the OEM, the suction port comes in the side of the tank. This conventional side-mounted method is bad news for water conservation. Once the pump sucks air over the top of the water line in the tank, the pump goes into the dry lock, and you cannot suck that last 1" or more out of the tank. That 1" of the tank is 5.8 gallons lost water that cannot be pumped on my size tank. That is a lot of water not to be able to use.
Here is the reworked pump suction; I can now use the entire tank and only lose 1 to 2 quarts I cannot suck out. This gave me 5.2 more gallons of usable water. This tank has a bottom-mounted low-point pocket with a strainer inside the tank. The OEM used this as the tank drain. If you look at the right side tank end, a gold brass plug is in a port. That is where my pump suction line used to go. Now I draw water from the low point pocket through the Tee. I am a stickler for clean water; there is no dirt or crud in my freshwater system. This has worked out well for many years.
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Hair washing, my wife has shorter hair. It does not touch her shoulders in length. Every morning she washes her hair. This is "her" thing and need. I am not going to try and talk her out of it... She devised a way to wash and rinse only using 16 oz. plastic coke bottle. She put a push-pull drinking spout on the end; it screwed right on. She goes in the bath sink each morning to draw water; the tank is warm from the night before. We always shut the heater off when not using hot water. Our water heater is right under the bath sink. She fills the bottle with no waste and goes to the kitchen sink to wash her hair. She can wet, shampoo, and rinse and still has some left in the bottles. She is also a water miser at washing dishes; we use real silverware and plates.
At the bathroom sink, I added ball valves in the faucet supply lines to adjust how much water comes out of the faucet. We have a mono-lever faucet, and it is way too easy to open it up to allow too much water to go down the drain. I also did this when we had the OEM 2-knob faucet also. Yes, you have to wait a few seconds to fill your cupped hands with water when rinsing, but I found the bath sink was one of our larger daily water waste areas. Washing your hands after every time you go potty almost uses more water than the quick toilet flush. But when we go into the boondocking mode, the faucet supply gets choked down, and the waste is very little. When on hookups, I can open the faucet supply back up.
We have a Sealand 110 china bowl toilet; they no longer make this smaller size. It also has a sprayer to rinse the bowl if needed rather than running the foot pedal using much more water to rinse stuck on paper. I have a large, more flat-bottom black tank, 32 gallons; I add 3 gallons of starter water to the tank while setting up camp. This comes from a blue rubber-made water jug, not the fresh tank. The parks we boondock camp in have shower and potty houses; there is just no power or water at the sites. During the day, I hike to the potty house to reduce the black tank use. The wife uses the camper. When we go to the dump station, we transfer any leftover water to the black to aid in dumping. I have never had the dreaded black pyramid.
We can go 8 to 9 days on the black tank before dumping.
We wash dishes once daily; I clean, wipe and scrape dishes until the night meal dish clean-up time comes which go in a dry wash tub. If the weather is good, we wash dishes in tubs on the picnic table; the water is hauled in the 3-gallon jugs and heated in a pot on the LP gas outside stove. If the weather is bad out/raining etc, the wife does them in the kitchen double bowl sink. She uses less water inside than we do washing outside. Dishwashing inside is about 1 to 1 1/2 gallons.
I shower every night, navy shower, wife showers every other day unless it is brutal heat during the day.
Being on a 34-gallon fresh tank supply, we can go 4 to 5 days before I top off the tank at the campsite with the 3-gallon fresh water jugs. We only boondock for 8 to 10 days before moving to the next boondocking site. I use the blue tote to take the grey water to the dump station every 3 to 4 days.
This works for our style of boondocking, which is about 40% of our camping. Most of our camping (50%) uses onboard tanks and changing camps every 4 to 5 days, and about 10% full hook up. We all camp differently; all is OK to fit everyone's needs.
Good discussion, folks.
John