Identification of Potential Sites for Rainwater Harvesting for Lower Indus Basin (Guddu – Sukkur Region)

Abstract

This study presents a comprehensive analysis of potential rainwater harvesting sites within the Lower Indus Basin, specifically focusing on the Guddu-Sukkur region. Utilizing a Multi-Criteria Analysis (MCA) and Analytical Hierarchy Process (AHP), the study integrates parameters such as land use, geology, rainfall, drainage density, slope, and groundwater storage change to identify optimal locations for rainwater harvesting. The total watershed area under investigation spans 12,381 sq. km, with average annual rainfall data sourced from 16 meteorological stations. The analysis reveals that 809 sq. km are highly suitable for rainwater harvesting, with nine specific locations identified for detailed hydrologic modeling. The Watershed Modeling System (WMS) and Hydrologic Engineering Center's Hydrologic Modeling System (HEC-HMS) were employed to simulate hydrological scenarios, including a 100-year design storm (193.02 mm) and average annual rainfall (124.85 mm), to design hydraulic structures and estimate potential water volumes. The integration of GRACE and TerraClimate data through Google Earth Engine provided critical insights into groundwater storage and annual changes, essential for sustainable water resource management. The study emphasizes the importance of a multi-disciplinary approach, combining advanced analytical techniques with industry expertise, to ensure the effective implementation of rainwater harvesting systems. Future recommendations include long-term monitoring, integration of climate change projections, socio-economic impact assessments, advanced hydrological modeling techniques, strengthening policy frameworks, and establishing pilot projects. This research provides a strong framework for enhancing water resource management in arid and semi-arid regions, contributing to the sustainability and resilience of water systems.