How should they determine which source to use where?

A project has access to two alternative water sources.

How should they determine which source to use where?
A . A project may not use two alternative water sources
B . Target the uses that require the least treatment first, such as toilet flushing or irrigation
C . Match uses by location: indoor sources to indoor uses, outdoor sources to outdoor uses
D . All sources should be treated to potable water standards and used to supplement the municipal supply

Answer: B

Explanation:

When a project has access to two alternative water sources, the strategy is to use the source that requires the least amount of treatment for applications where water quality is less critical. This approach is efficient and sustainable as it reduces the need for extensive treatment processes. For instance, using untreated rainwater for irrigation or treated greywater for toilet flushing makes practical and environmental sense1.

Reference: LEED v4: Interior Design + Construction Guide2

LEED v4 water efficiency credits and standards3