Use an adjustable shut-off nozzle which can be down to fine spray so that water flows only as needed. Turn it of at the faucet instead of the nozzle when finished to avoid leaks.
Use hose washers between spigots and water hoses to eliminate leaks.
Do not leave sprinklers or hoses unattended. 600 gallons or more can flow in only a few hours. Set a shut-off reminder to turn it off.
Check all hoses, connectors and spigots regularly.
Install ornamental water features, like fountains, only if the water is recycled.
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