Damage and destruction from tsunamis is the direct result
of three factors: inundation, wave impact on structures, and
erosion. Deaths occur by drowning and physical impact or
other trauma when people are caught in the turbulent,
debris-laden tsunami waves. Strong tsunami-induced
currents have led to the erosion of foundations and the
collapse of bridges and seawalls. Floatation and drag
forces have moved houses and overturned railroad cars.
Tsunami associated wave forces have demolished frame
buildings and other structures. Considerable damage also
is caused by floating debris, including boats, cars, and trees
that become dangerous projectiles that may crash into
buildings, piers, and other vehicles. Ships and port facilities
have been damaged by surge action caused by even weak
tsunamis. Fires resulting from oil spills or combustion
from damaged ships in port, or from ruptured coastal oil
storage and refinery facilities, can cause damage greater