Optimizing Water Resources Allocation Under Climate Change Scenarios: A Case of Great Ruaha River Subbasin, Tanzania, 2021

This study undertook extensive fieldwork and data collection in the Rufiji Basin, conducted from September 27th to October 8th, 2021. The primary objectives were to introduce the Research Assistants (RA’s) and the RESBEN project to the Rufiji Basin Water Board (RBWB), establish valuable contacts, select sample sites for qualitative work, and gain a comprehensive understanding of the district and catchments under examination. Key aims included the collection of climate data, hydrological reports, water abstraction data, and insights into local irrigation schemes and water abstraction points. The data collected during the first phase encompassed water abstraction records, rainfall data from 17 stations, streamflow data from 14 stations, borehole data including location, depths, and yields, and reservoir data such as turbine discharge, spillway discharge, net evaporation, and elevation-volume curves.
The study's main objective was to optimize water allocation among competing users in the Great Ruaha River subbasin. The research sought to answer critical questions concerning the effects of climate change on water availability, variations in surface and groundwater potential, and the optimization of water allocation considering diverse climatic and development circumstances. The study's results have been effectively shared to water users, watershed managers, and other stakeholders via a Systemic Adaptive Management (SAM) workshop.