Jökull - 01.01.2001, Page 91

Accidents and economic damage due to snow avalanches and landslides in Iceland
THE TOTAL COST DUE TO
AVALANCHES AND LANDSLIDES
Based on the above estimates, it is found that the total
direct and operational loss due to avalanche accidents
in Iceland following the accident in Neskaupstaður
in 1974, together with the cost of purchasing build-
ings and the construction cost of defence structures, is
about 5.8 billion IKR (72 million USD). This includes
the cost associated with the relocation of Súðavík, the
purchasing of houses in Hnífsdalur, the cost of de-
fence structures for Flateyri and Siglufjörður, and the
estimated cost of the structures which are under con-
struction in Neskaupstaður. About 3.3 billion IKR (41
million USD) of the total is direct economic loss due
to avalanches and landslides, whereas the cost of de-
fence structures and the cost of relocation in endan-
gered areas amounts to about 2.5 billion IKR (31 mil-
lion USD). Unaccounted costs may be roughly esti-
mated as an additional 500 million IKR (6.2 million
USD).
When the hypothetical cost of the 69 fatal
avalanche and landslide accidents in Iceland in the last
26 years as estimated above is added to the economic
loss and the cost of avalanche protection measures,
the total cost of avalanches and landslides in Iceland
during this period is found to be more than 13 billion
IKR (162 million USD).
AVALANCHE HAZARD AND
ACCEPTABLE RISK
Avalanche hazard zoning is the basis of most other
work on improving avalanche safety, including local
community planing and the design of avalanche pro-
tection measures where settlements have already been
located in dangerous areas. Some initial work was
done on evaluating the avalanche hazard for settle-
ments in Iceland after the Neskaupstaður accident in
1974 (see for example de Quervain, 1975), but this
work did not lead to a fundamental change in the rules
and regulations regarding avalanche safety in Iceland.
It was not until after the accidents in 1995 that it
was fully realised that a substantial number of people
in several Icelandic towns and villages live in areas
where avalanche risk is unacceptable. This realisation
led to a strengthening of the avalanche work group
at the Icelandic Meteorological Office (Magnússon,
1996, 1998, in press) and the office was given the re-
sponsibility for avalanche hazard zoning in Iceland.
In 1995 shortly after the catastrophic accident in
Súðavík research into hazard zoning was strength-
ened. A research project was started at the Univer-
sity of Icelend to establish the statistical foundations
af hazard zoning. The result of this effort was that
it would be advantageous to delineate hazard zones
based on individual risk. A technique for estimating
the risk due to avalanches was also proposed (Jónas-
son et al., 1999).
The acceptable risk for individuals living in
avalanche hazard areas was considered by avalanche
professionals, government officials and the local au-
thorities of the affected communities. Avalanche risk
is non-voluntary and avalanche accidents have a high
“risk aversion factor”. It is therefore desirable that
avalanche risk in inhabited areas is significantly less
than for example risk due to fatal traffic accidents or
the total risk of death by accidents for children. This
line of argument leads to an acceptable risk level due
to avalanches on the order of 0.2 to 0.5 fatal accidents
per year per 10 000 persons assuming that a risk aver-
sions factor in the range 5 to 2 compared to traffic ac-
cidents is adopted. Similar results can be obtained by
considering the value of life discussed above (based
on willingness to pay analysis) and finding a risk level
that should be virtually negligible for most persons.
A new regulation about hazard zoning and the
use of hazard zones in Iceland was issued in 2000
(Ministry for the Environment, 2000). This regula-
tion specifies three different hazard zones which are
designated with the letters “A”, “B”, “C”. The zones
are based on the concept of “local risk”, which is de-
fined as the yearly risk of death faced by an individ-
ual who stays all year round in an ordinary building
at a specific location. The actual risk experienced by
inhabitants of hazard areas depends on the proportion
of time they stay in different types of buildings and on
the additional safety provided by exceptionally strong
buildings. This will typically be about 75% of the
specified “local risk” for domestic houses and on the
order of 40% of the specified “local risk” for commer-
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