The subject article (Nelson and Mayo 2014) presents an overview of previous reports of interbasin flow in the Great Basin of the western United States. This Comment is presented by authors of a cited study (comprising chapters in one large report) on the Great Basin carbonate and alluvial aquifer system (GBCAAS; Heilweil and Brooks 2011; Masbruch et al. 2011; Sweetkind et al. 2011a, b), who agree that water budget imbalances alone are not enough to accurately quantify interbasin flow; however, it is proposed that statements made in the subject article about the GBCAAS report are inaccurate. The Comment authors appreciate the opportunity to clarify some statements made about the work.