The magnitude of the earthquake that struck Port au Prince
was 7.0 on the Richter scale, with an epicenter 15 kilometers from the city and
at a depth of 10 kilometers. In 1770 a powerful earthquake occurred, destroying
the city, but many years have passed and it has slipped from Haiti's national
memory.
In Israel the last destructive earthquake, with a magnitude
of 6.2 on the Richter scale, occurred in 1927. Its epicenter was the Dead Sea,
and its effects were felt in Jerusalem, Nablus, Jericho, Ramle and Tiberias,
resulting in 500 deaths and injuries to 700. An earthquake in 1837 killed 5,000
people. According to the Jewish historian Josephus Flavius, in 31 B.C.E.,
30,000 people lost their lives in an earthquake.
On average, a destructive earthquake takes place in Israel
once every 80 years, causing serious casualties and damage. The more time
passes since the previous earthquake, the closer we are to the next. In other
words, we are running out of time.
The news from Port au Prince suggests that the destruction
is complete - of buildings and infrastructure. The earthquake occurred in the
afternoon, at a time when schools and public buildings were empty.
The main concern in Israel is that an earthquake would
strike during hours when public buildings are populated. Most schools and
hospitals in Israel were constructed before new building codes - which take
into account the effects of earthquakes - were enacted. Moreover, some 50,000
residential buildings in Israel do not meet the new codes and are expected to
collapse in the event of an earthquake. Even though this fact is known by all
decision makers, nothing has been done to strengthen buildings and prevent them
turning into death traps.
Billions of shekels are invested in the defense budget, and
this is seen as an obvious investment, but reinforcing hospitals or schools so
they can withstand earthquakes and their aftermath receives no allotment. The
plan for installing safety cages in classrooms may be a move in the right
direction, but in practice their installation has not begun and the budget for
this will most likely be taken from the funds allotted for reinforcing
buildings.
It is important to note that public buildings will have to
serve as places of refuge for many after a disaster. Also, even though there
have been plans and government decisions, the program for reinforcing
buildings, especially in towns situated in high-risk areas - along the Jordan
Rift Valley and the Zevulun Valley - has not been promoted sufficiently.
It does not appear that in the coming decade the situation
will change, even though the danger of a powerful earthquake is no less than
that of a nuclear disaster - with the difference that we know that an
earthquake occurs on average every 80 years.
As part of the preparations it is possible to install a
national warning system. A proposal on this has been made to the relevant
ministers and the Finance Ministry. Such a system will not replace the
necessary strengthening of buildings, but can offer short-term warning to those
in endangered buildings. The system would provide warnings 10-60 seconds before
the shock waves reach the buildings, based on sensors placed along the
Afro-Syrian Rift, and record the movement of tectonic plates, sending the
information to a nerve center.
The distance of most of Israel's population from the rift
enables most residents to have at least a 20-second warning time. Twenty
additional seconds usually pass before the building begins to collapse. In
practice, this provides a 40-second window. The estimated cost of the system is
$20 million, with an additional $1 million per year for operation and
maintenance. The system is already operational in Japan, Taiwan, Turkey,
Romania, California, Italy and Mexico.
Science