BEACH EROSION ON YANAGISHIMA, CHIGASAKI-NAK AAND HISHINUMA COASTS DUE TO STROM WAVES DURING TYPHOON 1721

Abstract

 On October 23, Typhoon No. 21 hit the coasts in Sagami Bay, and storm waves were incident to the coasts. On the Yanagishima coast immediately east of the Sagami River, severe beach erosion occurred, and foundation stones of the wave dissipating works were scattered by storm waves. On the Chigasaki-naka coast, where beach nourishment has been carried out, damage was minimal compared with that on the Yanagishima coast. Furthermore, on the Hishinuma coast east of Chigasaki-naka coast, the walkway along the costline was severely eroded and destroyed by waves. On October 24, field observation was carried out in the area between the Sagami River mouth and the Hishinuma coast to investigate the field conditions of the eroded coasts after storm waves. In this study, the results of the field observation on the Yanagishima, Chigasaki-naka and Hishinuma coasts were shown.