Coastal Erosion as a Function of Sea Level Rise and Sediment Imbalance

Abstract

This study analyses the effects of coastal erosion in the city of Loíza, Puerto Rico, and how does the Carraízo Dam located at Trujillo Alto, Puerto Rico contributes to the sediment imbalance along the Loíza coast. The study centers on evaluating the hydrological impacts of anthropogenic disruption to the natural fluvial sediment transport dynamics, with emphasis on the alterations to the alluvial system and hydro morphological processes of the Río Grande of Loíza, resulting from the construction of the Carraízo Dam. Despite extensive research on mitigating coastal erosion, few studies have directly attributed shoreline degradation to dam construction. By analyzing the physical changes of the river using high-resolution bathymetric data and satellite imagery interpretation we can get preliminary results suggesting a correlation between coastal erosion and sediment imbalance cause by the Carraízo Dam high efficiency sediment retention. The reduction in sediment discharge not only accelerated shoreline retreat but also it exposed the riverbed material downstream, affecting the environment, communities, and families that live in nearby areas and on the coast of the Loíza municipality. Key Terms – Coastal Erosion, Carraízo Dam, Sediment Transportation, Bathymetric Data, Satellite Imagery, Anthropogenic Disruption.