 dishwasher dishwasher the average household does about 215 dishwasher loads per year most conventional dishwashers use about 10 gallons per load while energy star qualified models use about 5 gallons per load let your dishwasher do the work  wash only full loads the average american household uses about 23 of its water running the clothes and dish washer just one partially full load can waste 510 gallons of water consider replacing your older dishwasher with a new energy starapproved dishwasher and you could save about 5 gallons per load if you hand wash your dishes consider this running the average kitchen faucet for just four minutes can use the same amount of water as a conventional dishwasher be sure to scrape food residue from dishes instead of rinsing rinsing can waste 25 gallons per minute and most new dishwashers don t require it  indoor  