Estimates vary, but each person uses about 80-100 gallons of water per day. Are you surprised that the largest use of household water is to flush the toilet, and after that, to take showers and baths? That is why, in these days of water conservation, we are starting to see toilets and showers that use less water than before.

shower-head

Many local governments have laws that specify that water faucets, toilets, and showers only allow a certain amount of water flow per minute. Water agencies in some areas, such as here in Atlanta, Georgia, offer rebates if you install a water-efficient toilet. In fact, I just put in two new toilets and received a rebate of $100 for each. Yes, they really do use a lot less water. For your kitchen and bathroom faucets, if you look real close at the head of a faucet, you might see something like “1.0 gpm”, which means that the faucet head will allow water to flow at a maximum of 1.0 gallons per minute.

Here is a water consumption calculator.

Typical water use at home
Bath A “full tub” varies, of course, but 36 gallons is good average amount.
Tip: Taking a shower instead of a bath should save a good bit of water.
Shower Old showers used to use up to 5 gallons of water per minute. Water-saving shower heads produce about 2 gallons per minute.
Teeth brushing <1 gallon Newer bath faucets use about 1 gallon per minute, whereas older models use over 2 gallons.
Hands/face washing 1 gallon
Face/leg shaving 1 gallon
Dishwasher 6-16 gallons Newer, EnergyStar models use 6 gallons or less per wash cycle, whereas older dishwashers might use up to 16 gallons per cycle.
Dish washing by hand: About 8-27 gallons This all depends on how efficient you are at hand-washing dishes. Newer kitchen faucets use about 1.5-2 gallons per minutes, whereas older faucets use more.
Clothes washer 25 gallons/load for newer washers. Older models might use about 40 gallons per load.
Toilet flush 3 gallons. Most all new toilets use 1.6 gallons per flush, but many older toilets used about 4 gallons.
Glass of water 8 oz. per small glass (not counting water for Fido or your cats). Also not you will be using water for cooking.
Outdoor watering 2 gallons per minute, depending on the force of your outdoor faucet. This may not sound like too much but the large size of lawns and yards means outdoor water use can be a significant use of water.
Average Total 80-100 gallons per day!

source: USGS