strategies, which vary in their effectiveness
a. Strategies to modify the event include land-use zoning, hazard – resistant design and
engineering defences as well as diversion of lava flows (P: role of planners, engineers)
(7)
Modify the event- make the impact of the tectonic hazard event less severe
- Before the hazard strikes, long-term
- Relies on technology and planning systems which can be high cost, so is less likely to be
used in developing and emerging countries
- Most desirable form of management
What? Advantages Disadvantages
Land use - High risk areas to a - High value land isn’t - Agricultural areas
zoning hazard can be mapped damaged may still be
out to ensure this land - Inexpensive if done damaged
is not used for building before - Expensive if
- It could be agricultural infrastructure is infrastructure
or recreational instead built needs to be rebuilt
- High risk may be: - Removes people - Prevents economic
o On low-lying from high-risk areas development on
coasts some high-value
o Close to volcanoes land, e.g. coastal
o On areas of high tourism
ground-shaking - Requires strict,
and liquefaction enforced planning
risk rules
Aseismic - These are built to - Won’t collapse, - V. expensive, so
buildings withstand earthquake saving lives (saves unaffordable to LICs
shaking and have a people and - Often only aseismic
strong, flexible interior property) up to a certain
structure - Technology is magnitude
- e.g. cross bracing, widely used, so - Older buildings and
counter-weights, deep reliable low-income homes
foundations are rarely protected
Tsunami - Sea walls and - Dramatically - Can be overtopped
defences breakwaters can be reduces damage - Very high cost
used to stop tsunamis - Provides a sense of - Ugly and restrict
progressing a security use/development
damaging - at the coast
infrastructure on land
Lava - Lava flows in channels - Diverts lava out of - Only works for low
diversion away from urban, high harm's way VEI basaltic lava
value areas - Relatively low cost - The majority of
'killer' volcanoes