Sistema de suporte à decisão para implantação da 2ª etapa do sistema adutor do Agreste Pernambucano

Abstract

Droughts in the Northeast are well known, with the irregularity of rainfall being a constant in the region, such as the recent drought from 2015 to 2020, which took its reservoirs to extremely low levels. The Pernambucan Agreste, located in the Northeastern semiarid region, is considered one of the most critical areas in the country in terms of water security, due to extreme water scarcity and the pollution of its water bodies. The public power has been facing this problem with the implementation of large infrastructures, such as the São Francisco River Integration Project with the Northeastern Hydrographic Basins - PISF and the Pernambucan Agreste Adductor System - PAAS, which aim to strengthen the local water supply and ensure guarantee of water supply to the benefited population. The PAAS, already in final implementation in its first stage, is interconnected to the PISF through the Ramal do Agreste, inaugurated in 2021, as well as to other sources, aiming to supply with good quality water, when implemented in its entirety, 69 municipalities in the region, with an estimated population of more than 2 million people by the end of the plan in 2037. The present work aims to respond to the needs of regions with high water vulnerability and support the issue of planning and prioritizing the implementation of large hydraulic infrastructures, such as of the 2nd Stage of the PAAS, budgeted at around R$ 2.25 billion. To this end, a Decision Support System (DSS) was structured, supported by information present both in the Atlas Águas - Water Security of Urban Supply, launched by ANA – National Water and Basic Sanitation Agency in 2021, and in the Update of the Pernambuco State Water Resources Plan (PERH|PE), concluded in 2022 by SEINFRA-PE – Secretariat of Infrastructure and Water Resources of the State of Pernambuco. The Analytic Hierarchy Process (AHP) was selected and applied, a Multi-Criteria Decision Analysis (MCDA) methodology developed in the 1990s, to prioritize the implementation of the various parts of the project. Thus, variables distributed in five dimensions (human development, education and health, financial, water and ecosystem) were selected and weighted, with the support of a consultation to experts and managers involved in this theme, in order to optimize water security and the achievement of basic sanitation universalization goals, foreseen in the new regulatory framework sanctioned in July 2020. As the main result of this dissertation, a hierarchy is proposed for the implementation of the sections of the 2nd Stage of the PAAS, with the stretches from Belo Jardim to Brejo Madre de Deus, Bezerros to Bonito and Lajedo to Palmerina being, in that order, the first to implement, thus highlighting the need to prioritize water supply to regions with lower human development indices, as well as those most affected in terms of the quantitative and qualitative vulnerability of their sources and water production systems. These results are intended to support the decision-making of the management and collegiate bodies, at federal, state, and local levels, aiming at a sustainable management of water resources in the Agreste region of Pernambuco.