OBLIQUE BREAKWATERS FOR MULTI-PURPOSE BEACH RECREATION AND SHORE PROTECTION

摘要

Breakwaters, jetties, and groins have long been used in the littoral environment as port, navigation, shoreline stabilization and beach protection structures. Customarily however, the recreational benefits of structures such as these have been realized only incidentally. For example, jetties built solely to stabilize an inlet almost immediately attract surfers who exploit the break created by waves reflecting from the structure. This is the case at Sebastian Inlet, Florida, where the world renowned ‘First Peak’ was created when the north jetty was lengthened in the early 1970’s. Often when the waves elsewhere are too small to surf, one can rely on First Peak to be surfable. Also, under conditions of large, long-period swell, although the normally incident surfbreak elsewhere tends to ‘close-out’, not only is First Peak an excellent break, but sometimes a second and third surfable peak appear.