A project has a potable water source as well as two alternative water sources.

The best practice for using alternative water sources is to target the uses that require the least treatment first, such as irrigation, toilet flushing, and cooling tower makeup. This reduces the energy and cost associated with treating water to higher standards than necessary. Matching uses by location is not a requirement, nor is treating all alternative water sources to potable water standards.A project may use more than one alternative water source as long as they meet the applicable codes and standards.References: WE Credit Indoor Water Use Reduction, WE Credit Outdoor Water Use Reduction, WE Credit Cooling Tower Water Use1