The Issue of Prevention in a City Subject to Natural Hazards

Due to natural hazards being present, cities that are subject to these hazards have to focus on prevention. Since it’s impossible to prevent a natural disaster, cities must be prepared in order to limit the potential material damage and loss of human life resulting from such disasters.

The problem is that certain cities are poorly prepared and protected against natural disasters. These cities generally experience more damage and loss of human life than those that are better prepared.

There are several reasons why certain cities are poorly prepared to protect themselves from natural disasters.

• The existence of several types of natural hazards, each type requiring different planning and development.

• Since building-resistant infrastructures are extremely expensive, the quality and solidity of existing infrastructures, such as buildings, roads, and bridges, are a factor.

• The city’s population density is another factor. When a lot of people live on a limited territory, protecting them can be complicated.

• Certain natural disasters can be impossible to predict, such as tornadoes.

• Cities in developing countries do not always have the financial means or resources needed to be well prepared.

Natural disasters can have similar consequences:

• Material damage (damaged or destroyed infrastructure)

• Victims (deaths, disappearances, injuries, displacement, homelessness)

• Interruption of essential services (water, electricity, communications)

However, each type of natural disaster also has its own consequences.

Prevention is the best choice of action in the face of natural hazards. Although it’s impossible to stop or avoid a natural disaster, prevention helps reduce the consequences.

Various stakeholders can be involved in the search for solutions.

Cities can put various measures in place to ensure that they are well prepared in the event of a natural disaster:

• Informing the population of the risks and measures to take before, during and after a natural disaster

• Establishing an emergency plan and informing the population about it

• Establishing a monitoring system to predict natural disasters

• Establishing a warning system in case of a natural disaster makes it possible to evacuate the population at risk

• Putting in place building standards to ensure solid infrastructure

• Forbidding people from settling in at-risk areas and building neighbourhoods far from these areas

These preventive measures are used for most natural hazards. However, there are other measures specific to one or two natural hazards.

Here are certain measures that can be put in place to limit the damage from volcanic eruptions.

• Monitoring ground movements around volcanoes often makes it possible to predict a volcanic eruption and evacuate the population.

• Reinforcing certain buildings so that they can resist the accumulation of ash.

• Building anti-lava barriers close to volcanoes to redirect lava and mud flows and protect towns and fields around the volcano.

• Preparing emergency plans and evacuation plans to protect the populations at risk in the event of an eruption.

Here are certain measures that can be put in place to limit the damage from earthquakes:

• Setting up a system to detect and analyze seismic activity is useful, although such a system cannot predict the exact moment an earthquake will occur.

• Prioritizing earthquake-resistant building standards is essential for limiting material damage.

• Implementing preventive exercises is essential so that the population knows how to keep safe during an earthquake.

Here are a few measures that can be put in place to limit the damage from tsunamis:

• Establishing a system for detecting underwater earthquakes in order to assess the risk of a tsunami

• Implementing a tsunami warning system to alert coastal populations and evacuate at-risk zones

Here are a few measures that can be put in place to limit the damage from landslides:

• Identify at-risk slopes and avoid building homes and infrastructure there

• Be aware of events that could lead to landslides (earthquake, tsunami, flood, etc.)

• Monitor populated zones that are at risk and evaluate the need to preventively evacuate the people living there­

• Prevent landslides by implementing certain civil engineering measures (improving drainage, reducing the incline of a slope, etc.)

Here are a few measures that can be put in place to limit the damage from tornadoes:

• Monitor weather conditions to predict when the risk of tornadoes is very high. However, a tornado’s trajectory is impossible to determine in advance.

• Issue a tornado warning to alert the population to move to a safe location

• Know of safe places to go in the event of a tornado (basement, far from windows and exterior walls, etc.)

Here are certain measures that can be put in place to limit the damage from hurricanes, cyclones and typhoons:

• Track the progression of hurricanes, typhoons and cyclones is essential. Meteorologists can almost always predict their trajectory.

• Inform the population of the time the cyclone will hit their region and evacuate them if necessary

• Build seawalls along the coastline to restrain the waves and minimize flooding and damage

• Reforest the coastline to create a natural barrier against strong winds

• Prioritize construction on stilts to protect the buildings from floods

Here are certain measures that can be put in place to limit the damage from floods:

• Monitor waterways and the weather in order to predict floods a few days before they hit, and evacuate the population if necessary

• Avoid building in flood zones

• Prioritize building on stilts to protect the buildings

• Avoid building dams and canals around waterways that can overflow and cause flooding

• Improve the rainwater collection system

Here are certain measures that can be put in place to limit the damage from winter storms:

• Monitor weather predictions in order to warn the population of a possible winter storm

• Put in place a strategy to remove snow from roads as fast as possible

• Close certain locations (schools, stores, etc.) in order to reduce road use

• Close sections of roads that become too dangerous

Certain cities are more vulnerable to natural hazards than others. The level of development of the country where the city is located affects its ability to protect itself in the event of a natural disaster.

Developed countries have financial, material and technological resources that enable them to be prepared before, during and after a natural disaster. Developing countries often have fewer resources and larger populations to protect, which makes these populations very vulnerable to natural disasters. A person in a developing country has seven times more chance of dying during a natural disaster than a person in a developed country^[2].

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