The breakwaters of the large fishing ports and commercial harbors all around the island interfere with tidal flows and currents, altering patterns of silting and erosion so that some harbors have to be abandoned when their construction is barely complete.
而在各地陸續興建的大型漁港、商港，因無法順應潮流的變化，造成突堤效應，海岸侵蝕作用加劇，部分剛完工不久的港口，還未驗收就報廢了。