Buy a Low GPM High-Pressure Cleaning Machine
GPM (gallons per minute) is a direct measure of the amount of water used when the pressure washer is actively running. So in order to use less water, be sure to buy a pressure washer with a low GPM!
Use a heated pressure washer
Hot water will naturally clean faster and more efficiently than cold water.
Therefore, using hot water will reduce the amount of water needed to do the job. Adding soap to hot water will also increase efficiency and further reduce water usage.
Efficient cleaning
Implement effective cleaning strategies to help reduce water usage:
When you're not actively cleaning, lower the trigger
Clean in an efficient pattern that minimizes overlap (top to bottom)
Lower PSI when high pressure is not required
Actively notice and repair leaks or other plumbing failures
in conclusion
One of the main concerns about pressure washing is the amount of water used and the relative cost of consumption.