Not eligible if no non-potable water?

Update: We did ask GBCI about this credit and got the following response (we also have earned this credit for our project since the first post): "According to LEED addenda for LEED ID+C Reference Guide (http://www.usgbc.org/sites/default/files/LEED%20ID+C%20v4%20Reference%20Guide%20Tables%20-%201st%20edition_4-14-2017.pdf), the word "used" in the first paragraph of page 33 in the credit requirement has been replaced with "analyzed", so that the section reads: "Document how the above analysis informed building and site design decisions in the project’s OPR and BOD. Demonstrate how at least one on-site nonpotable water supply source was analyzed to reduce the burden on municipal supply or wastewater treatment systems by contributing to at least two of the water demand components listed above. Demonstrate how the analysis informed the design of the project, including the following, as applicable:" That said, project teams are required to analyze the possibility of using non-potable water (e.g. rainwater) for their projects and document it in Integrative Process Worksheet (http://www.usgbc.org/resources/integrative-process-worksheet). However, project teams are not required to use an actual non-potable water source in this credit."   Hope that clears up any related questions.