Addressing Sedimentation of Ecuador's Rio Chone Estuary: A Watershed Perspective

The Rio Chone estuary, located on the Pacific Coast of Ecuador, is subject to high sedimentation rates due to unsustainable agricultural practices and deforestation within its watershed. This report seeks to address sedimentation of the water body from a watershed perspective. The estuary’s biodiversity and value to human use is threatened, as some regions have seen accretion of up to seven meters of sediment over the assessed period of 21 years. We analyzed bathymetric data to ascertain the current rate of sedimentation. We then created a sediment budget for the watershed to identify which erosional processes were the largest contributors of sediment, and ran a sediment generation model to quantify the volume of sediment produced from surface water erosion. Finally, we modeled different land use scenarios to explore how changes in land use could affect erosion rates. Our work showed that sheetwash erosion is the dominant geomorphic process generating sediment in the watershed. We conclude that strategic implementation of soil conservation strategies on cultivated parcels and reforestation of fallowed degraded lands has the potential to mitigate high sheetwash erosion rates, and have a significant damping effect on future sedimentation of the Rio Chone estuary.