Environmental Impacts of Dam-Induced Land Use and Land Cover Changes in the Muvumba Catchment: Implications for Water Quality and Predictive Modelling

The study examined the environmental impacts of dam-induced land use and land cover (LULC) changes in the Muvumba Catchment, Eastern Rwanda. It addressed challenges arising from agricultural expansion, deforestation, water body alteration, and urban encroachment, which threaten biodiversity, soil stability, and water resources despite the developmental benefits of the Muvumba Dam. The objectives were to analyse spatial and temporal LULC changes, evaluate their environmental impacts, and generate predictive insights for sustainable catchment management.  A mixed-methods approach was adopted, integrating questionnaires, interviews, GIS, remote sensing techniques (NDVI, satellite imagery, supervised classification), and field validation. Data was collected from a census of 150 stakeholders and analysed using SPSS through descriptive statistics, correlation, regression, and ANOVA, GIS-based change detection and FRAGSTATS analyses. Results showed significant agricultural expansion, localised deforestation, wetland shrinkage, increased turbidity, and rapid settlement growth. Regression analysis confirmed that deforestation (β = 0.156, p = 0.022), agricultural expansion (β = 0.277, p = 0.000), water body alterations (β = 0.355, p = 0.000), and urban encroachment (β = 0.269, p= 0.000) significantly influence environmental impacts, with water body alterations having the strongest effect. The study concludes that while the Muvumba Dam enhances socio-economic development, it also increases environmental risks when land use is poorly managed. It recommends integrated land-use planning, strengthened environmental monitoring, protection of ecological buffer zones, and the application of GIS-based predictive modelling to support sustainable decision-making and long-term ecosystem conservation.