The Development and Application of Information System for Water Management and Allocation (SIGA) to a Negotiable Water Allocation Process in Brazil

SIGA (Information System for Water Management and Allocation) is a generalized water resources system developed to help the planning and operation of water resources systems. Based on a node-link water resource network, SIGA has simulation, optimization, hydrologic, and water quality models to simulate the impacts of management and allocation rules in a water resources system. This paper presents the formulation and components of SIGA and its application to water allocation in the Upper Jaguaribe river basin, in the Ceara state of Brazil. The water allocation in Ceara is based on a negotiable process that relies on technical information (reservoir storages, water demand, and availability scenarios) and participatory involvement of stakeholders. This paper presents the scenarios built in SIGA using two different methods of water system simulation showing possible improvements on the decisions by revealing the risks related to each allocation alternative.