Water recovery, or catchment, systems are efficient and ecologically sound manners to avoid using potable or drinking water for various water needs - including focalized irrigation and sprinkler systems. Catchment systems drastically reduce water bills by "recycling" collected rain water and then storing it in a containment tank where it remains available for use.
    In other forms of water recovery, similar designs collect "graywater" - water that drains from showers, baths, laundry, etc. - which is stored/filtered and then re-used as wastewater (toilets)  before flowing into a sewer or septic system.