An Evaluation of the Primary Causative Factors Affecting Durability of Flow Diversion Simple Weirs in Muchinga Province in Zambia

Abstract

The effectiveness of simple weirs and the ability of rural farmers to construct durable weirs are still areas of concern in rural areas in Zambia. The objective of this study is to investigate the factors contributing to the varying levels of durability of the simple weir structures used for the diversion of river flows. This study was conducted in 5 districts where 33 SWs located in similar geographical zones were analyzed for their longevity. The research delved into catchment and climatic variables, and the social and psychological perception of simple weirs. The study conducted interviews with key informants who were familiar with the use of SWs in 5 districts in Muchinga provinces between 26 December 2023 and 15 January 2024 using semi-structured questions. The findings of this study indicated that simple weirs constructed on relatively square-shaped catchments and narrow-shaped catchment areas were less vulnerable to damage and easy to operate and maintain. The study also found that climatic factors such as storm rainfall events had little impact on the operation and maintenance of these weirs in Muchinga province, as most sites are in the rainfall shadow while farmers` views about the structures varied from site to site. Overly, planning is necessary for implementing small or large irrigation structures.