We learned a lot about water conservation while backpacking. Having to carry and/or filter all of our water while hiking and overnight camping made us very aware of how much water we were using. We figured out how to wash our camping dishes (usually a cooking pot and two plates, cups and spoons) in less than one cup of water.
At EntropyPawsed, we have a hand pump well. This reminds us at least daily of our water usage. This daily reminder encouraged us to develop our current system of dish washing in which we use about one gallon of water to wash the dishes.
Instead of filling the sink, we pour about a quart of water into a small rectangular container that fits down in the sink. We prop the far end of the container on the back of the sink, so that all the water in the container collects in the front. We add to the water a fair amount of a non-toxic, biodegradable dish detergent. After all, soap is what kills any germs!
We put another quart of water into our tea kettle to heat on the stove top, then add one or two cups of the hot water to the water in the sink container. This creates a pool of water deep enough to wash the dishes. We have a double sink; we put the water container in one side and the dirty dishes in the other.
We put rinse water in a recycled plastic litre bottle with a drinking spout. This gives us greater control over how much water comes out of the bottle. Those who want to avoid plastic could use a glass bottle or a ceramic or metal pitcher instead.
We usually lick obvious food particles off our utensils, then place them in the sink container to soak. While we sometimes also lick our own plates and bowls, we also allow our dog and cat to lick them. Yes, we know many others who do this (including my mother!) and, no, there aren't any diseases we can catch from this.
We wash the drinking glasses and cups first, when the water is the cleanest. When rinsing a dish, we make sure the rinse water flows over and into the dirty dishes in the sink. We then use this rinse water to pre-wash the dishes, thereby keeping the wash water clean.
About halfway through the dish washing process, we frequently add to the wash water a little more hot water from the kettle, and refill the rinse water bottle. If we have a lot of dishes, we may need to fill the rinse bottle a third time.
We prefer to allow the dishes to air dry. We think this is more hygienic and definitely less labor intensive.
According to the EnergyStar website, the average dish washing machine uses 4 to 6 gallons of water per cycle. Plus, the website states that some households use up to 20 gallons of water pre-rinsing dishes prior to placing them in the dishwasher.
In a time of resource depletion with impending energy shortages, we think it prudent to be aware of, and appropriately modify, all our resource usage.