Decision support system for sustainable management of water resources in addressing the problems of global climate change

• Grant number: 22/15693-0
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Effective date (Start): February 01, 2023
• Effective date (End): September 30, 2026
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Principal Investigator: Ricardo César Aoki Hirata
• Grantee: Fernando Schuh Rörig
• Host Institution: Instituto de Geociências (IGC). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 20/15434-0 - SACRE: integrated water solutions for resilient cities, AP.TEM

Abstract

The occurrence of extreme events and periods of drought in Brazil has jeopardized the water supply of adequate quality and quantity to multiple users. Such pressures require an Integrated Water Resources Management that answers to socioeconomic and environmental changes in a specific area and considers the diverse stakeholders, making water and territory management compatible. Water problems also demand engineering and/or nature-based solutions, which incorporate environmental processes to manage the environment and water resources adequately. Strategies to improve water security need to consider economic aspects and their benefits, including the value of the benefits provided by ecosystems to society (ecological services), as well as a realistic view of the losses and costs involved. For this purpose, cost-benefit analyses allow the comparison of solutions and their impacts on the various water users, which need to be readily available to decision-makers, considering the sensitivity to various climatic, institutional, environmental, economic, and technological scenarios. In the upper part of the Bauru and Batalha river basins, in the state of São Paulo, problems such as the vulnerability of public water supply to droughts, the intense extraction on the Guarani Aquifer System, and the contamination of the Bauru Aquifer System demand interventions and policies to guarantee local water security, also aiming at maintaining the base flow and ecological functions. Thus, the project seeks to develop an economic analysis of the costs and benefits of socioeconomic solutions for maintaining and improving water security, considering surface and groundwater bodies and engineering, management, and nature-based solutions, under different scenarios and associated uncertainties. The study area covers the upper part of the Bauru and Batalha Rivers basins, which covers the municipalities of Bauru, Piratininga, and Agudos. The main objectives are: a) to identify and propose measures for improving water security in the region; b) to value the ecosystem services provided in the watersheds, including indications for economic payment mechanisms; c) to identify long-term strategies in the socioeconomic, environmental and legal spheres for improving water security and; d) to establish an integrated analysis model to guide managers on practices for efficient use of environmental resources and an increase in water security. The project will cover the following methodological steps: i) the evaluation of qualitative and quantitative problems in the region; ii) the proposal of solution alternatives for the existing problems; iii) the estimation of costs and benefits of the selected alternatives, considering the provision of ecosystem services, which will be valued and will bring subsidies for economic payment systems; and iv) the identification of the best alternatives for water security, considering the displaying to stakeholders of a Decision Support System, allowing the visualization and validation of the results for the different possible scenarios. Thus, the project aims to present solutions to current water security problems affecting the State of São Paulo and other regions of Brazil, highlighting the role of groundwater. An innovative character is using analytical tools with stakeholders to evaluate strategies such as the conjunctive use of surface and groundwater and nature-based solutions, which require assessments of their gains and losses in the integrated water management resources. (AU)