River erosion mitigation innovation: Field study of permeable groins made from used tires

River erosion can be accelerated by factors such as high current velocity, easily eroded soil types, and human activities. One of the mitigation methods used is permeable groins to reduce current velocity and control flow patterns. However, the use of conventional materials is often expensive and difficult to obtain. This study tested the effectiveness of permeable groins made from used tires in reducing river erosion. The study was conducted in one of the rivers in Jambi City that experienced severe erosion conditions. Permeable groins were installed on site, and measurements were taken for one month to evaluate current velocity, riverbed elevation, and sedimentation. Arduino was used in this study to measure time-series discharge during the study period. The results showed that the installation of groins from used tires was able to reduce the average current velocity by 35 % and facilitate sediment accumulation of up to 6.16 cm between the groin structures. However, local erosion occurred on the groin piles due to the acceleration of the flow through the gaps, which caused an increase in erosion depth of up to 9.95 cm in some areas. In addition to technical benefits, the use of used tires also helps reduce waste and construction costs, making it an economical and environmentally friendly alternative solution.