I don’t know what those folks are doing but we use maybe 3 gallons hand washing
It's marketing hype from the dishwasher companies. They appear to be measuring it as if you keep the rinse water running all the time while sloooowly doing dishes by hand. lol.
Meanwhile, water isn't bad for septic systems, the phosphates in the soaps are though. Only concerns are desert climate areas. So make sure you use a septic safe soap regardless of how you wash dishes. And same for laundry soap.
They're trying to paint themselves as "green"
disregarding all the materials and energy it costs to produce the thing in the first place and probably disregarding the power to run it. Not that I'm against them per se. But it's marketing. The total ecological impact HAS TO BE lower for doing them by hand. Just say'n.
Besides if you're in an area with a septic, you probably have well water too. So it's mostly about HOT water usage, and the dishwasher is probably a bit lower with a full load of dishes on those costs. So if you only run it with a full load, and you don't use the dry cycle (more electricity), and you heat your water for hand-washing economically, it's a "wash" (Ha!).
But if you add in the cost of making and transporting and recycling the dang thing, or you use the dry cycle, or run it more often than when full, I don't see it as a win at all. At best they can save water in the desert where Tweety lives and has to worry about such things.
They also get billed as "more sanitary" and that's probably true too, but it costs electricity to heat that water and run it around. If you let the dishes dry overnight, the dry dishes are sanitary too. It's the dry air that kills the best, as long as they're clean and don't have any fat residue on them.
They are nice though. I can almost guarantee my electric bill would go UP not down though, and that's after the cost of the thing and the cost of the soap.
