Producing Valuable Information from Hydrologic Models of Nature-Based Solutions for Water

This paper applies an evaluation framework of salience (type of information), credibility (quality of information), and legitimacy (trustworthiness of information) to assess how hydrologic modeling outputs have been used in NbS projects by three types of decision makers: advocates, implementers, and analysts. Authors' findings, based on documents and interviews with watershed management programs in South America currently implementing NbS, consider how hydrologic modeling supports two types of decisions for NbS projects: quantifying the hydrologic impact of potential and existing NbS and prioritizing where NbS might be sited within a watershed. To help inform future modeling studies, authors identify several problematic assumptions that analysts may make about the credibility of modeled outputs for NbS when advocates and implementers are not effectively engaged. Authors find that credible, salient, and legitimate results in applications evaluating NbS for water are not always generated in the absence of clear communication and engagement.