In 1927, the city of Santa Barbara, California, began construction of a rubble mound breakwater to create a protected yacht harbor. The initial breakwater was an L-shaped structure that left a gap between the short “arm” of the breakwater and the shore, and engineers believed this configuration would allow sand to continue its normal movement along the coast. 1 The engineers who designed the structure acknowledged that, “The design of a harbor on a sandy coast is one of the most difficult problems of engineering.” They anticipated some shoaling of the harbor and erosion of the beach to the east, particularly during storms. 2 Their report framed the breakwater as an experiment in which trial-and-error would lead to an ideal harbor for the city, but they downplayed both risks and costs involved, including projecting that “the annual cost for maintenance will be negligible.” 3 This optimism would prove badly misguided, as sand almost immediately began to fill the new harbor.
Joanna Dyl (Sun,) studied this question.