Toilet use accounts for 25 to 30% of household water use. If you don’t have a newer high-efficiency toilet there is something you can do to reduce the amount of water needed to flush. Fill a plastic half-gallon milk jug with small rocks and/or sand and replace the cap. Place the jug in the toilet tank. Make sure the jug does not interfere with the flushing mechanism or the flow of water. This will save a half-gallon of water per flush.
A leaky toilet can waste as much as 200 gallons of water a day. Place a few drops of red food coloring in the toilet tank. Check the toilet bowl in an hour or two, or let sit over night. If the bowl shows any red, you have a leaky toilet.
A small drip from your faucet will add many gallons of extra water to your system each day. Repair all leaks as soon as possible. Faucet aerators and high-efficiency showerheads reduce water use thereby reducing the amount of water entering your system.