Wash the car on the grass or use a commercial car wash where the water is recycled.
Stay away from installing an ornamental water feature such as a fountain unless the water is recycled. Be sure to place it in area away from windy areas and direct sun to avoid evaporation loss.
Install a water-saving pool filter that uses less water during back flushing.
Keep a cover on the pool to avoid evaporation.
Use reclaimed or reuse water where available for irrigation.