Model calibration and hydraulic assessment of a water supply macrosystem with desalinated water integration

Abstract

Hydraulic projects and infrastructures are of high relevance for regions characterized by water scarcity, since modifications in their structures, which are interconnected and interdependent, may generate adverse impacts throughout the entire system. In this context, modeling and calibration emerge as fundamental tools for scenario forecasting and for proposing improvements in these water infrastructures, especially in water distribution networks, which involve multiple elements and high levels of complexity. It is noteworthy that the Fortaleza Metropolitan Region, due to its high population density and a climatic regime marked by water scarcity, is particularly susceptible to impacts associated with prolonged drought scenarios. The present thesis aims to discuss and analyze a new water supply source, specifically desalination, and its impacts on the distribution network, through the proposal of a calibrated model of the macrosystem and the simulation of the injection of desalinated water under different scenarios of water demand growth. For the development of the calibration and auxiliary functions, codes implemented in MATLAB were used, while EPANET was employed for the hydraulic modeling of the network. The results obtained highlight the innovative nature of the adopted approach and emphasize the importance of scenario forecasting based on calibrated water distribution system models. Furthermore, the results suggest that, in the long term, the water supply of a densely populated region may present limitations when sustained by only one or a few supply sources. In addition, it is concluded that the introduction of a new water supply source into the network does not, by itself, guarantee equity in meeting minimum hydraulic requirements and may intensify social inequalities in access to water.