Survive on Your Own for 3 Days After a Disaster! The Truth About the 72 Hours Without Relief Supplies

Hello!SONAEAREBA here.

Nankai Trough Earthquake and
Tokyo Inland Earthquake probabilities are rising, and I want to talk about the

harsh reality we face. When a disaster occurs, government support will not arrive in full force until at least 4 days after the event, meaning you must

survive entirely on your own for those 72 hours


without any help.

Why does it take 4 days for support to arrive? Understanding the limits of government

The first 72 hours are prioritized for "life-saving and rescue operations"

The 72 hours after a disaster is the period when life-saving and rescue operations are the top priority for the government, police, and fire departments. During this time, rescue teams focus all their efforts on saving people trapped under rubble or inside buildings, so the distribution of supplies to evacuation centers and support for victims is pushed to the back burner.

According to data from the Great Hanshin-Awaji Earthquake by the Ministry of Land, Infrastructure, Transport and Tourism's Kinki Regional Development Bureau,

the rescue rate on the day of the earthquake was 75%, but it dropped significantly to
24% the next day, 15% on the third day, and 5% on the fourth day. As these figures show, survival rates drop drastically after 72 hours, so during this period, they


have no choice but to focus on life-saving

. Reference link: NHK WEB Special 2025/1/14 "It was the residents who did the rescuing"

Support for people unable to return home also begins in earnest from the 4th day

As clearly indicated in government guidelines, government agencies and others will focus on life-saving, rescue, and firefighting activities for the first 3 days after a disaster, and will transition to a system for supporting people unable to return home from the 4th day onwards. In other words, the support system for disaster victims will only be fully established

from the 4th day onwards

. Reference link: Cabinet Office, Disaster Management



"Guidelines for Measures for People Unable to Return Home Following a Large-Scale Earthquake"

The harsh reality shown by the latest damage estimates

Latest estimates for a Tokyo Inland Earthquake

In the latest damage estimates released by the Tokyo Metropolitan Government in 2022, it is predicted that

if a Tokyo Inland Earthquake occurs, the number of evacuees could reach
approximately 2.99 million. The prediction that the number of evacuees arriving at shelters will peak between 4 days and 1 week after the earthquake, when household stockpiles run out, speaks volumes about the situation we should be preparing for.

Of particular note is the possibility that after 3 days have passed since the earthquake, more people who were sheltering at home will run out of supplies and begin to evacuate to shelters. This indicates that many people have only prepared 3 days' worth of supplies, predicting a serious shortage of goods from the 4th day onwards.

Reference link: NHK Metropolitan Area Navi

"Tokyo Inland Earthquake: Tokyo Metropolitan Government revises damage estimates, 'Disaster Scenario' in detail"

The threat of a Nankai Trough Earthquake

In the new damage estimates for the
Nankai Trough Earthquake published in March 2025, a maximum of
298,000 casualties are expected.


707 municipalities across 1 metropolis, 2 urban prefectures, and 26 prefectures have been designated as areas that need to implement earthquake disaster prevention measures, and due to the scale of the event, delays in the distribution of relief supplies are certain.

Reference link:
Japan Meteorological Agency website
"About the Nankai Trough Earthquake"

Concrete preparations to survive 72 hours

Securing water: The top priority for survival

It is said that the limit for humans to survive without drinking water is
72 hours, and
this is the standard for disaster response.

What I recommend is
3 liters per person per day,
a stockpile of at least 7 days' worth of water.
3 days' worth is highly likely to be insufficient.

Restoring lifelines takes time, and
for about a week after the disaster, there is a
possibility that lifelines such as electricity, gas, and water will be cut off.

In particular, water outages tend to be prolonged, so
it is also important to
secure water for daily use, such as by filling the bathtub.

Food stockpiling: The reality that 9 meals are not enough

The Ministry of Agriculture, Forestry and Fisheries guidelines state that
"Immediately after a disaster, it is assumed that public supplies from the government will not arrive for at least 3 days due to severed transportation networks, etc., so secure at least 3 days' worth (9 meals) of food"

.
However, considering actual disaster response, this is clearly insufficient.
If we assume unprecedented situations such as a Nankai Trough earthquake or a Tokyo inland earthquake,


I believe that at least 7 days' worth


,
and preferably 2 weeks' worth of food stockpiles are necessary. Emergency food tends to be biased toward carbohydrates, so it is important to combine staple foods (rice, bread, noodles), main dishes (canned goods, retort-pouch foods), and side dishes (vegetable juice, canned fruit)


in a balanced manner.

Securing a heat source: For cooking and heating

In situations where electricity and gas cannot be used,
a portable gas stove and gas canisters
become a lifeline.

For each portable gas stove,
you should have at least 10 gas canisters ready.
With this much, you will be able to cook warm meals and
boil water.

The reality of evacuation centers: Comfort cannot be expected

Confusion immediately after opening an evacuation center

From immediately after the disaster until around the second day, when the management of the evacuation center has just begun,
it is expected that
they will not be able to handle food distribution
because many people will be evacuating.
It is thought that soup kitchens and the like will begin from the third day onwards, but since food is distributed with priority given to those requiring special care such as pregnant women, children, and the elderly, healthy adults will be left for later.

What I am particularly worried about is
the overcrowding of evacuation centers.

In terms of ensuring privacy,
staying at home evacuating at home is clearly
superior.

However, if you choose to evacuate at home,
there is a disadvantage that support information from the government and municipalities is
hard to reach.

Possibility that infectious disease countermeasures will delay support

It is also assumed that rescue activities may be delayed due to measures to prevent infectious diseases such as COVID-19, or conversely, that responses to infectious diseases may become insufficient due to rescue activities.
This means that life in evacuation centers will become even more difficult.

The importance of the option of evacuating at home

Ensuring the safety of your home

Local disaster prevention centers opened when a disaster occurs
cannot provide enough space if many people evacuate, so
assuming your home is safe,
sheltering at home is the principle.

To achieve this, advance measures such as installing furniture fall prevention devices and applying shatterproof film to glass are important.
pre-disaster measures are important.

I strongly recommend that you
check the seismic resistance of your home in advance and
carry out reinforcement work if necessary.

There is a significant difference in the seismic resistance of buildings built around 1981,
so those living in older buildings
need to be especially careful.

Reference link:
Tokyo Disaster Prevention Homepage"Sheltering at home"

Building a cooperative system with neighbors

To succeed in sheltering at home,
cooperation with neighbors is essential.

Like the efforts of the Futamatagawa New Town Second Neighborhood Association,
a safety confirmation system using yellow flags and information exchange through
disaster prevention picnics are very effective.
Reference link:

Town News
"Protecting the community from disasters"

Latest earthquake probability and the urgency of preparation

Probability of a Nankai Trough earthquake

Following the magnitude 7.1 earthquake that occurred off the coast of Hyuga-nada on August 8, 2024,
the Japan Meteorological Agency issued the first Nankai Trough Earthquake Extra Information

"Megaquake Advisory".The probability of a Nankai Trough earthquake occurring within the next 30 years is about 80%,

and it is now in a situation where it

"could happen at any time."

Past case studies have confirmed cases where a larger earthquake occurred after a large-scale earthquake,
and there is even a case that occurred 14 days later.
This shows that you cannot let your guard down

even after the alert period has passed.

Imminence of a Tokyo inland earthquake

Regarding a Tokyo inland earthquake,
it is predicted to occur with a 70% probability within the next 30 years.
In the worst-case scenario, it is estimated that there will be approximately 23,000 deaths and 95 trillion yen in economic damage,

and the impact will extend to all of Japan.
Reference link:
NHK WEB 2024.06.11



What is the damage estimate for a "Tokyo inland earthquake"?

What we can do right now

Reviewing and expanding stockpiles

While many households havea 3-day supplyprepared,
few households havea 7-day supply or more.
I recommend increasing your stockpile in stages.

First, check your current stockpile, make up for any shortages,
and gradually expand it to a 7-day supply, and then a 2-week supply.

Utilizing the rolling stock method

It is important to manage stockpiled food
by utilizing the rolling stock method.
This is a method of purchasing more of the food you use in your daily life,

consuming the oldest items first, and replenishing only what you have used.
This allows you to
always maintain a fresh supply of stockpiled food.

Sharing information with family

It is important to decide on
contact methods and meeting places with your family

in advance in case of a disaster.
Assuming that mobile phones may not work,
learn how to use the

disaster emergency message dial.
Also, confirm the walking routes from
each family member's workplace or school to
home, and be aware of the locations of disaster return-home support stations.

Measures at companies and schools

Stockpiling and stay-in-place plans at the workplace

In the event of a Tokyo inland earthquake,
it is predicted that up to 8 million people
will have difficulty returning home.

Companies and schools need to prepare
sufficient stockpiles so that employees and students
can safely remain at their workplace or school.

Government guidelines recommend staying
at the workplace for 3 days after a disaster,
and it is the company's responsibility to secure
water, food, blankets, and other necessities during that time.

Formulating a phased return-home plan

Regarding returning home from the 4th day onwards,
it is recommended that a staggered return,
rather than a simultaneous one,

should be the standard.
Companies need to formulate phased return-home plans
that consider employees' residential areas and transportation, and establish a system to avoid confusion.

The importance of local communities

Collaboration between self-help, mutual aid, and public aid

The basics of disaster response are said to be
70% self-help, 20% mutual aid, and 10% public aid.
In other words, personal preparation is the most important,

followed by mutual aid among local residents,
and finally, government support (public aid)
is added to the structure.

Especially in the 72 hours after a disaster,
public aid can hardly be expected,
so it is necessary to get by with self-help and mutual aid.

Only those who have protected their own and their family's safety can provide mutual aid. There is no mutual aid without self-help.
Keep these words in mind,
and first, prioritize
ensuring the safety of yourself and your family.

Active participation in disaster drills

It is important to actively participate in
disaster drills conducted in the community and acquire
the skills necessary in an actual disaster.

Firefighting drills, first aid training, and evacuation guidance drills
will definitely be useful in an actual disaster.

Summary: Better safe than sorry

You cannot expect government support for 4 days after a disaster.
Also,

the people who support local disaster prevention are

victims who, like us, have families of their own. Accepting this harsh reality, it is important to start preparing to protect

the lives of yourself and your family right now.

Nankai Trough Earthquake and Tokyo inland earthquake are
only a matter of time,
and it will be too late to panic when they happen.

In addition to securing water, food, and heat sources,
safety measures for your home, building a cooperative system with the community, and other
multifaceted preparations are necessary.

What we can do is limited, but
with solid preparation, it is possible to
overcome the long 72-hour period.

Even if you open your mouth and look up during a disaster, rice balls won't fall from the sky.
Keep these words in your heart, and start taking action today.

Preparation for disasters
is never a waste.

Even if a major disaster does not occur,
you can utilize stockpiled food in your daily life
and deepen local bonds.

Better safe than sorry.
Now is the time to seriously review your disaster preparations.

Partitions for evacuation centers set up by local governments

Not cardboard or a tent, a "new space"
"Airtore" will change evacuation centers in Japan.

Carry "peace of mind" inside your bag.