This document contains digital supplementary material (characterization of the case-studies, developed simulation models (and final configurations), optimisation models and post-processing assessments) related to the article entitled “The Paradigm of Water and Energy Integration Systems (WEIS): Methodology and Performance Indicators”, which is part of the peer reviewed conference proceeding of the 35th European Symposium on Computer Aided Process Engineering (ESCAPE 35). The present content has been adapted from the PhD thesis entitled "Simulation and Optimisation of Water and Energy Integration Systems (WEIS): An Innovative Approach for Process Industries".