Análise e sugestões para diretrizes de uso das disponibilidades hídricas superficiais da Bacia Hidrográfica do Rio Piancó, situada no Estado da Paraíba.

Abstract

The Coremas-Mãe D’Água reservoirs system, with capacity of 1.4 hm3, is located in the Piancó river basin, within the semiarid region of Paraiba state, and presents water allocation management conflicts among its multiple users. This system is responsible to meet the demands of several urban water supply, irrigation and fishing activities, hydropower energy generation and flow regularization to Rio Grande de Norte state, which is the main conflict. The management importance of this complex system is reflected by the Agencia Nacional de Água (ANA), the Departamento Nacional de Obras Contra a Seca (DNOCS) and the two states representatives joint action to establish the Curemas-Açu river basins Regulatory Mark to define criteria, norms and ways to deal with its water use conflicts. The aim of this work is to analyze the system’s water availability, including the operation of 24 upstream reservoirs and their use in an integrated way, to provide information to help establishing management polices to the Piancó river basin system. The system was analyzed for the nowadays physical, operational and hydrologic behavior scenario and created ones, including a 10 m3/s São Francisco river water diversion. Three hydrologic conceptual models were used, being one of them specially developed to simulate the Coremas-Mãe D’Água behavior. The regulated flow concept as a parameter to establish water uses and operating actions is not recommended to integrated systems due its variation according to river basin upstream interventions, reservoir operations and conceptual modeling. The total downstream irrigation demand requirement was not met for two years planning horizon with the actual situation. The São Francisco water diversion support would give to the Coremas-Mãe D’Água system the capability to meet all the required irrigation demand for the two years planned time horizon.