Assessment of Physical Status of The Irrigation Structures in Nyarubogo Irrigation Scheme, Rwanda

Abstract

The physical status of irrigation structures holds immense importance in ensuring the efficient and sustainable management of water resources for agricultural purposes. This study aimed to assess the physical status of the Nyarubogo irrigation scheme structures, which has implications for the level of performance of this irrigation scheme. Specifically, the study assessed the effectiveness of the irrigation infrastructures in terms of intake efficiency, canal physical condition, and command area development. Cross sectional study design was employed, and units for the study were randomly selected to be included in this study. Observation method were used to characterize the physical condition of the Nyarubogo irrigation scheme while questionnaire survey were used to collect data on the implication of socioeconomic characteristics on the performance, and effectiveness of irrigation system.  The collected data were fitted to the irrigation structures assessment approaches suggested by Bos, Zende and Nagarajan. Analysis of farmer’s responses was through Statistical Package for the Social Sciences (Version 27).  This study evaluated the physical status of about 130 irrigation structures in Nyarubogo irrigation scheme. The structures included 7 division boxes, 73 water drops, 2 aqueducts, 42 turnouts, 4 bridges, and 2 Culverts. Overall, the scheme had an effectiveness of 63.8%, with culverts, bridges, and water drops presenting more than the average functional condition of 64.38%, 75.00%, and 100.00%, respectively. The intake efficiency during this study was found to be 67% accumulated from efficiencies of sediment level (20%), embankment (35%), and sluice gate (12%) based on their weightage percentage and rank scores. The overall canal condition was good and was quantified to 70%. The command area development was exhibiting subpar performance, registering a mere 32% effectiveness. Moreover, the study evaluated how farmers' socio-economic status influenced the inadequate maintenance of the Nyarubogo irrigation systems. It uncovered numerous elements contributing to this dilemma: there was limited engagement of women and youth in agricultural pursuits, low educational attainment, challenges surrounding land ownership (specifically, land tenure), the small size of land holdings per household and a notable absence of government incentives for maintenance efforts. These factors, however, when coupled with inadequate funds derived from water fees, significantly obstruct the proper care of these irrigation infrastructures. On the other hand, high runoff due to heavy rainfall was mentioned by the majority of farmers (20.7%) among the primary causes of poor maintenance of irrigation structures. Generally, the evaluation of the Nyarubogo irrigation system structures emphasizes the uneven levels of efficacy and challenges, highlighting the necessity of focused maintenance efforts and enhanced water management techniques.