Study on Coastal Environment Impact Assessment Method for Shore Protection Facilities

This study aims at establishing an environment impact assessment method for coasts where physical and habitat environments may be influenced by the construction of coastal conservation structures such as seawalls and breakwaters. A conceptual coastal life and plants inhabitation model across a sandy beach, as well as the impact-response relations between coastal life and plants and typical maritime structures are constituted on the basis of field surveying data at more than 11 coasts in Japan. Considerations and procedures on selecting representative species and dominant impact factors for environment evaluation are then discussed. Finally, an integrated coastal environment impact evaluation model is constructed by combing coastal hydrodynamic models and HEP (Habitat Evaluation Procedure) technique. The developed model is applied to simulating the habitat suitability of clams around breakwaters at Toban coast of Japan. Comparisons between the simulated results and measured data indicate that the model can give reasonable habitat impact evaluation.