What is a Hazard Map?

— A 'Disaster Prevention Map' you should check first to protect your life from disasters —

When choosing a house or land, many people prioritize price, location, and the surrounding environment.

However, 'disaster risk' is just as important.

In recent years, natural disasters such as heavy rain, large typhoons, and earthquakes have been increasing, and it is not uncommon for disasters to occur even in 'areas that have never suffered damage before'.

This is where the 'hazard maps' published by local governments come in handy.

Hazard maps show the assumed disaster risks for each region, such as floods and landslides.

In this article, we will clearly organize the characteristics of each disaster and the points you should check on a hazard map.

🌊 Flood Hazard Map

Characteristics

This is a disaster where rivers overflow due to heavy rain or typhoons, causing residential areas and farmland to be flooded.

Inundation can last from several hours to several days, having a major impact not only on buildings and roads but also on lifelines.

Points to check

✅ Assumed inundation area for your home

✅ Assumed inundation depth (how many meters of flooding)

✅ Route to the evacuation center

✅ Distance from rivers

🌧 Inland Water Hazard Map

Characteristics

This is a disaster where rain exceeds the capacity of sewers and drainage facilities, causing roads and residential areas to be flooded.

Since it can occur even if rivers do not overflow, special caution is required in urban areas.

Check points

✅ Areas prone to road flooding

✅ Areas around underground facilities

✅ Low-lying areas with poor drainage

✅ Commuting and school routes

🌊 Storm Surge Hazard Map

Characteristics

A disaster where sea levels rise due to typhoons or low pressure, causing seawater to flow onto land.

Wide areas along the coast can be flooded, and damage is even greater if it coincides with high tide.

Check points

✅ Coastal flooding zones

✅ Estimated flood depth

✅ Location of seawalls

✅ Evacuation routes to higher ground

🌊 Tsunami Hazard Map

Characteristics

A disaster where a tsunami generated by a large earthquake rushes from the coast inland.

It can arrive in a short time and may strike multiple times rather than just once.

Check points

✅ Tsunami inundation forecast areas

✅ Tsunami evacuation site

✅ Evacuation route to high ground

✅ Arrival time

⛰ Sediment disaster hazard map

Features

This is a disaster where slopes collapse or debris flows occur due to heavy rain or earthquakes.

Since it can lead to significant damage in a short time once it occurs, extra caution is needed in mountainous areas.

Check points

✅ Sediment disaster alert area (Yellow Zone)

✅ Sediment disaster special alert area (Red Zone)

✅ Distance from cliffs and mountain streams

✅ Evacuation direction

🏚 Earthquake hazard map

Features

Although the content varies by municipality,

・Susceptibility to shaking

・Possibility of liquefaction

・Active faults

can be checked.

It is useful not only for building collapse but also for preparing for secondary disasters such as fires and liquefaction.

Checklist points

✅ Estimated seismic intensity

✅ Liquefaction risk

✅ Location of active faults

✅ Designated evacuation shelters

👀 Points to check when looking at a hazard map

Do not just check your own home.

Make sure to check the following locations as well.

📍 Workplace

📍 School

📍 Commute route

📍 Frequently visited facilities

Furthermore,

✔ Evacuation shelters

✔ Evacuation routes

✔ Meeting places for your family

Deciding these in advance will help you act calmly during a disaster.

⚠ Things to keep in mind regarding hazard maps

✔ Areas without color are not necessarily completely safe

✔ There is a possibility of disasters exceeding the estimated scale

✔ Check the latest version on your local government's website

✔ Review it periodically

It is important to think of a hazard map not as a "map that guarantees safety," but as a "map for understanding disaster risks."

🌱 Summary

Hazard maps are essential information for building a home or choosing land.

The points to look for differ depending on the disaster, but

🏞 Flooding

🌧 Inland flooding

🌊 Storm surge

🌊 Tsunami

⛰ Sediment disaster

🏚 Earthquake

Checking each risk in advance will help ensure the safety of yourself and your family.

When choosing land or a home, don't forget to consider "disaster preparedness" in addition to "price" and "convenience."