Why does Japan face water shortages despite being an island nation?

Why does Japan face water shortages despite being an island nation?

A new water infrastructure concept created with seawater, recycled water, and renewable energy

Japan is an island nation surrounded by the sea on all four sides.

Nevertheless, we see news about water shortages almost every year.

When it doesn't rain, water restrictions begin, agricultural water runs short, and some regions suffer from the impact on crops.

In recent years, climate change has altered rainfall patterns, making extreme situations where it either rains heavily in one place or hardly at all in another no longer rare.

Furthermore, dams across the country are aging, and in some places, their original water storage capacity has decreased due to sediment that has accumulated over many years.

In other words, Japan's water infrastructure still relies on the premise that:

it will rain.

However, Japan has another major water source.

That is the ocean.

Although Japan's seawater desalination technology is said to be world-class, its domestic use is limited to only a small portion.

I believe we should be utilizing this ocean more actively.

This is a concept to distribute seawater desalination facilities along the coast and develop them into regional infrastructure that generates water, electricity, and resources, rather than just water supply facilities.

Seawater is purified through advanced pretreatment and then desalinated using reverse osmosis (RO) membranes.

Instead of using that water once and discarding it, we circulate it within the city by repeatedly undergoing sewage treatment, advanced purification, and reuse.

Industrial water.

Agricultural water.

Water for toilets and cleaning.

Environmental water.

And after advanced treatment, it can also be considered for use as tap water.

In other words, it is a society that does not treat water as 'disposable'.

Furthermore, there is a pressure difference in the pipes that transport water.

If this energy, which is usually lost through pressure reduction, can be recovered using small-scale hydroelectric power generation devices, we can reduce the power consumption of the entire facility while transporting water.

This is not so much about creating new energy as it is about effectively utilizing energy that was previously discarded.

The seawater desalination facility itself can also be reimagined.

The entire facility can be covered with a pyramid-shaped solar power generation structure, and vertical-axis wind turbines can be distributed outdoors.

Solar power during the day.

Wind power when the wind blows.

Water pressure recovery when water flows.

By combining multiple renewable energy sources, the energy efficiency of the entire facility can be increased.

A desalination facility is a power-consuming installation, but by combining it with renewable energy, we can reduce dependence on purchased electricity and, depending on conditions, expand the possibilities for utilizing surplus power.

Furthermore, the concentrated brine generated by seawater desalination is not just waste.

Natural salt.

Magnesium.

Calcium.

Other minerals.

If these can be recovered as resources, they could also become a new source of revenue.

In other words, this facility would simultaneously fulfill three roles:

• producing water

• utilizing electricity effectively

• recovering resources

as well.

If such facilities were distributed along coastlines nationwide, we could create regional water supply hubs instead of relying on centralized systems.

This would also allow for risk diversification during disasters, offering significant benefits for disaster prevention.

Of course, this concept requires an initial investment.

However, if we can supply water, utilize energy effectively, and generate resources as byproducts, there is a possibility of recovering the investment from a long-term perspective.

In the coming era of advancing climate change, what we need is not just infrastructure that assumes it will rain.

We must utilize the ocean as a stable water source, circulate water, and ensure that neither energy nor resources go to waste.

Isn't such a self-circulating infrastructure the new social foundation that Japan should aim for?

Author

Unemployed middle-aged man

Cooperating AI

ChatGPT

Publication Month

August 2026

Copyright and Scope of Use

The copyright for the manga images, characters, text, and composition of this work belongs to the author.

Please refrain from reprinting, reproducing, redistributing, modifying, publishing, or selling all or part of this work without the author's permission.

When introducing this work, please include a link to the original post. Viewing and saving for personal enjoyment is permitted.

Keywords

Seawater desalination, water shortage, Japan's water issues, water cycle, sewage reuse, reclaimed water, reverse osmosis membrane, RO membrane, hydraulic power generation, small-scale hydropower, renewable energy, solar power generation, vertical axis wind power generation, circular society, natural salt, mineral recovery, decentralized infrastructure, disaster prevention, water resources, climate change

Hashtags

#WaterShortage #SeawaterDesalination #WaterCycle #ReclaimedWater #ClimateChange #RenewableEnergy #SolarPower #WindPower #Hydropower #DecentralizedInfrastructure #DisasterPrevention #Environment #Japan #FutureTechnology #UnemployedMiddleAgedMan #ChatGPT