To fill tanks when on anchorage I use a 20 gal bladder in the bottom of the dingy with a small 12 V transfer pump. Lot easier than lugging 5 Gal water cans.
A lot of really good ideas have been posted already.
We currently sail the Red Sea and water is a real issue here... especially GOOD water. We have 300 liters in 3 different tanks and no watermaker. We can go 2 weeks on anchor without a refill. We also carry emergency jerry jugs on deck. When Manny built our forward water tank he made two separate tanks with hoses that lead to two taps in a locker. These hoses lead to one main hose which leads to a junction with tank # 3 and the water pump. This allows us to closely monitor our water when we are not at dock. We open one tap and when that tank runs dry we know we have used 1/3 of our water supply, next tap means ˝ and we open the tap to our 3rd and last tank. At that point we know we need to refill soon. This method keeps everybody onboard aware of water usage.
Two things will use up your fresh water more than anything else. Doing dishes and taking showers. (Of course, any heads that run on fresh water must have the option to switch to salt water when underway.)
Our galley has a foot pump. Our head does not, because it wasn’t feasible to install one. Underway we close the electric pumps and only use the galley foot pump. We have a salt water tap, wash dishes with salt water and give a short rinse with fresh water at the end. We have tested this system against using only fresh water and the electric pump. We found we use 1/3 the water.
One excellent tip I got a few years back is to dilute your dish washing soap with water. Most detergents are very dense and require a lot of rinsing to get the soap off. Diluted dish soap cleans just as well and requires a lot less rinsing. (You also save on the detergent
) We avoid cooking pasta underway because we haven’t found a way to cook it without using tons of water. Maybe you can come up with an inventive piece of advice there
. We agree with twd and steam veggies, although most of our offshore cooking is of the one pot type. We wash fresh produce and and rinse grains in salt water.
Over here we are fortunate and can jump in the water for cruiser showers any time of the year. We soap up and give a QUICK rinse with our cockpit shower. When we were cruising in northern latitudes I would boil water in the kettle and wet a washcloth. That was enough to wash my face in the morning. Using a wash cloth, I can sponge bath in a cup of water. Honestly, not being stingy, but I prefer this to handi wipes.
In the Bahamas I was the rain (wo)man. My favourite job was catching rain water. We often topped up our tanks in a squall. And if it really rained hard, our dingy would fill up and then we had a party. I’d climb in the dinghy with the laundry and soap and we’d all get clean. I miss rain!!!!