Water losses and performance of receiving reservoirs of the PISF in Paraiba River basin

Abstract

According to the water scarcity situation in the semiarid region, the São Francisco River Integration Project (PISF) was undertaken to mitigate these problems. The Paraíba River basin benefits from the PISF East Axis, which from the municipality of Monteiro/PB is transported through the Paraíba river. This way of transposing the waters entails considerable water and financial losses to the system. The objective of this work is to evaluate water losses in transit on the river bed and by evaporation of four reservoirs located along the Paraíba river, when considering the water transposition of the São Francisco river (Project of Integration of São Francisco river - PISF).  Two system´s operation scenarios were considered: 1- considering the current form of the PISF flow transportation (through the river bed), 2- considering part of the flow being transported by pipelines to the water treatment plant of Gravatá. Considering the above scenarios using water restrictions established by the 87th Joint Resolution of the National Water Agency – ANA and the Paraíba Water Resources Management Executive Agency – AESA. A multiobjective optimization model, based on successive linear programming, was used when considering the period of time from 2012 to 2017, which was marked by severe drought in the region. The system performance was evaluated through the use of indicators related to the meeting water demands and the efficiency of reservoirs. Scenario considering pipeline were more efficient, either regarding to the water demand supply or water losses and that increased demand is possible at certain points in the system.