Coastal Numerical Modeling of Peninsula Beach, California

The coastal and Hydraulics Laboratory (CHL) at the U.S. Army Engineer Research and Development Center (ERDC) and U.S. Army Engineers Los Angeles District have recently completed a beach and shoreline preservation study for the Peninsula Beach, California. The aim of the study was to prevent the excessive shoreline erosion at the site by investigating numerical modeling solutions of different alternatives for preserving the beach. Numerical simulations were performed using the Coastal Modeling System (CMS) developed by the Coastal Inlets Research Program (CIRP) at CHL. The CMS consists of a two-dimensional (2D) circulation and sediment transport model coupled with a spectral wave model. Five alternatives including submerged groins, submerged reef, and advanced beach fill are evaluated by comparison of calculated morphologic and shoreline changes coupled with the hydrodynamics for an average annual sediment transport rate. The study results helped the City of Long Beach in designing shoreline protection alternatives to reduce frequency and volume of the periodic beach nourishment.