Electronic Theses and Dissertation

Abstrak krueng baro river is a river that has headwaters of beungga districts tangse which empties into the town of sigli with ± 52 km length and the basic area 355.07 km2 width. nowadays, the river is already degraded, it’s quite dangerous for the banks, or the riverbank. it is caused by sand excavation carried out by people in both the upstream and downstream. the aim of the research is to estimate the sediment production on any flood events and to estimate the safety factor of the slope in the area that became a mining excavation c with ± 1208.40 m length. the scope covers writing basic explanation of the cause of the degradation of rivers, streams transverse profile measurements, the depiction of the results of measurements, analysis of flood discharge, analiasis flow speed and security analysis slope on sand mining area. calculation formula manning equation analyzed by flow rate obtained each transverse profile with an average discharge of q = 391.78 m3 / sec . sediment transport is calculated by equation approach graf and schocklitsh equation . the total amount of suspended sediment discharge qs = 0.200 tons / day or 0.123 m3dan basic sediment load ( bed load ) qs = 732.65 m3 at each flood event . the amount of mining was done to ± 18.36 m3 / day in 6 months to ± 1648.80 m3 , within one year of 3297.60 m3 . from the comparison of sediment transport and mining , then the lack of sediment of ± 2566.33 m3, there is a deepening of the riverbed or degradation. calculation of slope stability (safety factor) are analyzed with bishop slices method approach. from the calculation results obtained fs> 1.25, meaning the slope of the river is still in safe condition. for prevention riverbed degradation government must socialize production estimates of sediment at each occurrence of floods and the community take the sand does not exceed the resulting sediment production as well as for the prevention of sliding riverbanks should be made masonry retaining cliffs of concrete or building installation slower current protectors or by planting trees cliff river. keywords: degradation, sediment discharge, slope stability.