Natural Hazards: Causes and Effects - Disaster Management Center ...

of population from rural to urban areas, and a decline in the number of skilled workers in rural
areas. How governments and development agencies respond to these changes can have a
major impact on future development. 13
Impact on Land
After an earthquake there is usually a substantial impact on land values, land controls, and
sometimes land tenure. Typically land values increase especially in urban areas and even in
marginal areas. The cost of land is driven up because of the increased demand for “safe” sites
for rebuilding. There may be a large number of people who have lost their land or who live on
sites still threatened by aftershocks. Since earthquakes have no effect on agriculture,
agricultural lands may experience the same increase in price as urban land.
Pre-disaster Activities
Fortunately, a great deal can be done to prevent earthquakes from becoming disasters. First,
the general public as well as engineers, planners, politicians and others need to understand the
nature of earthquakes. Based on that understanding, a decision and various levels of
commitment are needed to implement measures to mitigate earthquake damage.
The first level of commitment requires that government and policymakers create strategic
development and investment programs. A comprehensive approach would establish
geographic zones and a target population.
A second level is design of an extensive public awareness program. This program informs the
public about the earthquake hazard and illustrates what can be done to prevent a disaster.
The third level is a technical assistance program. This could include architectural and
engineering assistance in improved building design, construction, and siting; training local
residents in these techniques; and conducting projects that demonstrate the nature of these
techniques.
The implematation of these mitigation measures must be preceded by collection of background
information. 14
There are many ways to reduce earthquake damage. Possible actions include:
• Developing construction techniques that are seismic resistant;
• Conducting a program to introduce improved construction techniques to the building industry
and the general public;
• Analyzing soil type and geological structure to determine which sites are safe for
construction;
• Instituting incentives to remove unsafe buildings and buildings on unsafe sites or, more
probable, to upgrade their level of safety;
• Instituting incentives to encourage future development on safer sites and safer methods of
construction through:
– land-use control (zoning);
– building codes and standards and means of enforcing them;
– favorable taxation, loans or subsidies to qualifying and building methods sites;
– land development incentives.
• Reducing possible damage from secondary effects by:
– identifying potential landslide sites and restricting construction in those areas;