Shoreline Change at Mañagaha, Saipan

Abstract

The coastlines of the world are the focus of population growth and urban development this century. It is projected that approximately 2.65 billion people will be living within the coastal zone by 2025. More than half of all Americans now live on or close to the coast with population density expected to increase. Within the Pacific Basin, population growth can increase the economic incentive to develop more land. On islands, this results in development pressures along the shoreline and into the active beach system. Chronic erosion of the shoreline increases resource and population vulnerability to inundation by storm surge, tsunami, and sea-level rise. As population increases along the coastline, the need to understand the highly dynamic coastal region becomes more important. The majority of shoreline change studies have been prompted by realization that coastal erosion threatens private property, public infrastructure, and natural ecosystems (National Academy Study, 1990). Improved understanding of detailed erosion patterns provides managers with a basis for planning appropriate coastal development and resource management, thus improving community resiliency and sustainability. Lack of robust physical processes modeling means that analysis of historical shoreline trends provides a practical, relatively affordable method of predicting future erosion hazards (National Academy Study, 1990). Typically, studies compile and analyze historic and modern shoreline position data to inform planning and policy about past shoreline variability. The methods used are designed to record, analyze, and predict patterns of shoreline change. These are largely dictated by the physical characteristics of the shoreline being studied and the type and quantity of shoreline position data available.