Since “throughflow analysis is similar to input–output analysis”, according to Zhang et al. (2010), it is listed in this category as well. Throughflow analysis may not be too familiar in the industrial ecology field, as it stems from natural ecology. However, due to the comparable nature of the two systems, man-made ecosystems and natural ecosystems, it has been borrowed and applied to a few urban case studies.

“Throughflow analysis investigates the relationship between environmental inputs and compartmental throughflows” (Ma and Kazanci 2012), accounting for the matter and energy flows departing from compartments, and measures both direct and indirect flows with a matrix (Matamba et al. 2009; Zhang, Yang, and Fath 2010). The compartments that are referred to here have to be previously defined, which can be done with an ecological network analysis or they can become evident from the relevant sectors that emerge in the input-output tables. For example, in the study of an urban water metabolic system the identified compartments were local environment, rainwater collection, industry, agriculture, domestic sector, and wastewater recycling (Zhang, Yang, and Fath 2010).