While large breaking waves are rare, the force of the waves can destroy buildings, piers, bridges, and other structures. Even relatively small waves can cause strong currents which in San Francisco and Los Angeles have caused millions of dollars in damage, principally by fishing boats and yachts breaking free and colliding with each other and harbor structures. Damage can also be caused through battering by water-carried debris such as logs, boats, autos, etc. The retreating waves can scour the support for bridges, piers, breakwaters, etc., and cause their failure. Chemical spills and fires caused by ruptured storage tanks are also common.
Waves can travel long distances up rivers as bores.
It is important to include search and rescue in emergency plans as often rescues at sea are possible. Reports of some events are apparently incomplete such as the 1831 event which had effects observed in Trinidad and St. Christopher, but not by locations in between. Similarly, the 1842 tsunami was reported as destructive waves at Haiti, and 3.1 m waves in the Virgin Islands, but while the earthquake did damage in P'uerto Rico, no tsunami is reported from there. It was also reported from Grenada, Bequia Island, and Guadeloupe. F. Tsunami History.