Sedimentation processes have negative socioeconomic and environmental consequences, ranging from eutrophication phenomena, loss of water quality in surface water bodies, effects on the potential for hydroelectric generation, etc. Frequently, anthropic activity is the main cause that enhances these processes through changes in land use that can lead to landscape modifications. Therefore, it is relevant to evaluate this phenomenon and to be able to discriminate the influence of different land uses on the contributions to sediment loads at different scales. The novel Compound Specific Stable Isotopes technique allows the evaluation of sediment inputs associated with different land use changes in a study region. In the present work this technique was used in the Alhajuela Lake sub-basin, within the Panama Canal Watershed. The contribution levels of three (3) representative land uses (forest, pasture and sediment) in the study area were evaluated for the sediments present in sixteen (16) selected mixing points. The main contributions of the sources to the sediments present in the main rivers and tributaries flowing into Alhajuela Lake, in the sub-basin of the same name, were identified. The results obtained are consistent with observations and measurements of sedimentation in the study area.