The WaterSense label or local equivalent requirement in Water Efficiency Prerequisite, Indoor Water Use Reduction...

The WaterSense label, or a local equivalent, is a requirement for the Water Efficiency Prerequisite, Indoor Water Use Reduction in LEED v4 ID+C. This label ensures that eligible newly installed plumbing fixtures are both water-efficient and high-performing. The use of WaterSense labeled products is part of the strategy to reduce aggregate water use by 20% from the baseline12.

References:

LEED v4 Indoor Water Use Reduction Calculator3.

LEED v4: Interior Design + Construction Guide4.

LEED v4 water efficiency credits: Do you know the new standards?1.

LEED QUALIFICATION GUIDE - v42.