10 gallons per person per day is very generous. I would expect that you have to work hard to reach that consumption.

We use an average of 10 gallons per day. That level of consumption is more typical with a water maker. We can make 40 gallons per hour. We shower daily, use water as we please, occasionally use the water to rinse the cockpit and deck and use lots of water to rinse scuba equipment.


Warren S/V Scuba Doo
Lagoon 50 (winner of best crewed yacht under 55 feet at the St. Thomas crewed yacht boat show).

https://www.cyabrochure.com/ebn/2307/pdyrX/6642/4///