His Imperial Highness the Crown Prince of Japan Keynote Lecture High Level Panel on Water and Disasters The 8th World Water Forum

March 19th, 2018
Convention Center Ulysses Guimarães
Brasilia, Brazil

Water to bring about prosperity, peace and happiness

Your Excellency Dr. Han Seung-soo, Chair of HELP,
Your Excellency Mr. Janos Ader, President of Hungary,
Excellencies, Ladies and Gentlemen,


It is my great pleasure to give the keynote lecture at the 8th World Water Forum held here in Brasilia, the federal capital of the Federative Republic of Brazil, a country of abundance and development. Before I continue, I would like to note that many regions of the world, including Asia, the Americas, Europe, Africa, Pacific States, and small island states were hit by severe water related disasters last year. In Japan, a heavy rain hit the Kyushu region and had a grave impact. I would like to express my deep condolences and sympathy to all of the victims and affected people. I sincerely hope that the disaster-affected areas from the previous disasters will recover and be restored as quickly as possible.

2.Water as the foundation of regional and national prosperity

Brazil is also a country of openness. It has warmly received a large number of immigrants from all around the world. This year, Brazil and Japan commemorate the 110th anniversary of Japanese immigration to Brazil. I would like to express my sincere respect to all people who have contributed to the prosperity and development of Brazil.

I learned that many who immigrated here have engaged themselves in reclamation and farming. The vast, fertile lands that grow crops and abundant water resources were prerequisites to this end.

In this country, there are extensive rainforest areas which serve a critical function for the global carbon cycle, great rivers such as the Amazon and the Rio de la Plata, as well as massive aquifers such as the Guarani that lies beneath Brazil and extends across borders. These water related areas play important roles not only in the growth and development of the country but also in balancing climate and conserving biodiversity on the earth.

In all regions and countries, water is one of the indispensable elements for sustaining the livelihoods of people and the development of society. Water, however, has not been freely available throughout history. This is a fact of human history that people have relentlessly worked with water to accomplish their prosperity, peace and happiness.

3.Water for economic and social development

Let us look at a concrete example. This picture shows the Meiji Water System in central Japan which I visited in 2014(Picture.1). The water system runs through the Anjo Plateau where people suffered a chronic water shortage during the Edo Period. The people fought over water in the barren land.

In the early 1800s, Yakoh Tsuzuki, a wealthy farmer, conceptualized a large-scale irrigation project in the plateau. The concept was materialized a half century later by his followers (Fig.1). The large project was called the Meiji Water System (Fig.2) and has transformed the area into one of the leading agricultural districts in the nation as shown in this picture (Picture.2). I visited the watershed management office of the area in 2014 and witnessed that smooth and stable water supply to the beneficiary areas continues till today through ensuring proper water management operation by water level monitoring and accurate and appropriate water allocation. This is a good example of how water has significantly contributed to the development of regional economies and society.

Let me cite another example. When discussing and taking action on water, we, who have been involved in water, tend to focus too much on water itself, but we should also really pay more attention to issues beyond those of water. Campo Cerrado shown in this picture is a vast plateau area including Brasilia (Picture.3). This area that covers a quarter of Brazilian territory was once considered as dry and non-productive wasteland. Years of research have revealed that the low productivity is attributable not to the shortage of water but to the composition of the soil. Development efforts to cultivate Cerrado were embarked upon with a focus on soil amelioration and seed improvement. The utilization of rain water, irrigation and other water measures were applied where necessary. With these efforts, Cerrado was transformed into a highly productive agricultural zone (Picture.4).

Yesterday, I revisited the Cerrado Agricultural Research Center, or CPAC, 36 years after my first visit in 1982 (Picture.5,6). I was deeply impressed by the abiding ardent determination of researchers from Brazil and Japan, and their continuous endeavors to transform Cerrado. This graph shows the total annual production of soybeans in Cerrado and non-Cerrado areas of Brazil (Fig.3). This shows the total production of cotton (Fig.4). The dreams of the people I witnessed 36 years ago have come true, and Cerrado has now evolved into one of the leading agricultural zones in the world.

A nexus of water, food, energy and ecosystem is being advocated in the international community. Cross-sectoral collaboration is emphasized. New horizons of development will open up for us by promoting close cooperation between people from the water sector and people from other sectors.

4.Sharing water

Let me touch upon the importance of sharing water.

This picture shows Sanbu-ichi-Yusui or “Triple spring water divide” that has been used in Yamanashi Prefecture, Japan since the Edo Period (Picture.7). The spring produces 8,500 cubic meters of water a day and supports rich agricultural production in the area.

The spring water originates from a watershed in the south of Yatsugatake Mountain Range as shown in this picture (Picture.8). The mountain range extends as far as 30 kilometers from north to south, and 15 kilometers from east to west. Yatsugatake, which was an active volcano, has virgin forests, meadows and lakes in the north. The southern part of the range has steep slopes and peaks as high as 2,500 meters or more. Yatsugatake is a popular mountain range and is also one of my favorites. I have climbed mountains of the range three times including the highest one, Mt. Akadake, which is 2,899 meters high. I took this photo from Mt. Amigasa at the southern tip of the Yatsugatake Mountain Range in September 2005 (Picture.9). The rocky mountain on the left is Mt. Akadake and on the right is Mt. Gongendake. As you can see in the picture, the mountains are very steep. You will realize the steepness if you climb these mountains. I drank pristine water from the Maiden Spring in the area during the mountain climbing (Picture.10). It was quite cold and very refreshing.

The geology of the southern mountains mainly consists of porous lava rocks and lapilli. Rain water and melted water from snow easily infiltrate into the ground and become ground water. There are many springs at the altitude of 1,100 meters as the ground water accumulates over the impermeable clay layer. Despite the existence of spring water, water shortage was severe in the plateau below as there were no major rivers. Since people had to rely on a limited amount of spring water for their farming, communities fought over water. On the other hand, debris flow called On-dashi, meaning “pushing out” in the local language, frequently hit the area when heavy rain occurred. On-dashi often washed away irrigation channels and weirs. This picture shows a stone as large as six meters which was pushed out of the valley by On-dashi in 1943 (Picture.11). People inscribed the disastrous event on the stone in order to hand it down to posterity.

Please look at this figure (Fig.5). This old document from 1725 is an agreement among communities concerning the changing of intakes and water distribution routes after a debris flow buried a weir upstream. The change of the water route is drawn on the attached map (Fig.6). This detailed agreement indicates that distribution of water was a matter of life and death for the communities.

The name of Sanbu-ichi-Yusui or “Triple spring water divide” suggests people’s efforts and ingenuity to share water wisely. Sanbu-ichi means “one third”. The triple spring water divide distributes spring water equally to three downstream communities. Spring water is first gathered in a water reservoir. As shown in this picture, a triangular “water divide stone” is placed in the center of the reservoir so that a streamlined flow enables equal distribution of water (Picture.12). The position of the device, which was formerly a wooden post, was not originally fixed so that people could try changing the position until they were convinced that water was equally distributed. The fixed stone in its current shape and position indicates that people had a long-term discussion of trial and error in order to form a consensus. It is noteworthy that water is equally distributed in a visual manner as transparency counts in sharing water. The community members take turns in patrolling watercourses as water guards in order that this equally-distributed precious water does not get stolen or lost from broken water channels.

This picture shows an imaginary white snake (Picture.13). The local legend tells that On-dashi occurred in the Edo Period. This huge white snake was carried from the mountains. The snake disappeared when the disaster was over, but it may incur the wrath of the white snake if anybody deforests the water source area or tampers with the triple spring water divide. This is presumably community wisdom to protect water and their water source.

As we have seen here, the people of the community have succeeded in managing droughts and water related disasters, sharing water and mitigating conflicts by discussing at length, ingeniously devising structures and methods and ensuring transparency. This enriching and charming triple spring water divide symbolizes the sharing of water in a peaceful manner.

This is just one example from Japan, but there are many good practices and experiences of sharing water around the world and throughout history. Ingenuity for sharing water can be found not only in structures as well as in customs but also in social systems, laws and regulations, and treaties and conventions. These examples suggest that sharing information, collaborating to protect water and water sources, and compromising on different uses of water are the first steps to achieve sharing of water, prosperity, peace and happiness.


5.A role water has in the prosperity on the earth - a perspective through the advancing eyes of science and technology -

We have seen examples of communities and peoples towards prosperity and peace by working with and sharing water. Now, through the eyes of science and technology, I would like to show a broader role water plays in achieving and ensuring prosperity on the planet.

This picture is an observation tower in Manaus, Brazil (Picture.14). It observes the atmospheric boundary layer above the forests. This is a picture of a similar tower in Yakutsk, Russia (Picture.15). The observation by these towers helps reveal the movement of air and heat on the earth and the role water plays in the process.

You may have experienced the cooling of air when gardens and streets are watered in summer. In Japan, this is called Uchi-mizu (Picture.16). The cooling phenomenon happens as water absorbs substantial heat from the ground surface when it is turned from liquid into vapor. The vapor rises up into the air. This phenomenon also occurs on a global scale (Fig.7). The surface of the earth, including the ocean surface, is heated by the sun. Water and moisture on the earth’s surface absorb heat when turning into vapor. After that, the vapor rises up into the air. The vapor is condensed and turned into raindrops. Finally, after the rain, the dry air comes back to the earth’s surface. The process prevents overheating of the earth’s surface. It also creates air and heat circulation in the troposphere.

By contrast, oceanic water moves by the sea currents (Fig.8). Through the process, warmed water in the tropical zones releases heat in the frigid zones and warms the continents there. This means that massive heat circulates around the earth as the sea water moves.

Overall, heat circulates round the earth vertically and horizontally with the help of water. Without this vertical and horizontal movement of water, the earth would be overheated and divided into extremely hot zones and cold zones, making our world uninhabitable (Fig.9).

Global air movement created by water helps the formation of the natural environment on the earth. The Amazon watershed is well-known for its rainforests and diverse ecosystem (Fig.10). The Amazon receives a tremendous amount of rainfall, which washes away phosphorus, the nutrient in the soil, out to the sea. One would think that phosphorus, necessary for sustaining the ecosystem, will eventually be depleted. As you all know, however, the rich ecosystem on the fertile ground of the Amazon has been sustained for a long time. Why is this so? The answer is in Africa.

This map observed from a satellite shows the amount of dust transported by the air (Fig.11). You can see that large amount of dust which is blown up from the Bodele Depression in the African Sahara is carried by a grand air current across the Atlantic Ocean. This dust, rich in phosphorus, falls on the South American continent. It is estimated from the satellite observation that the amount of dust falling on the continent amounts to 45 million tons per year, including the 27 million tons that fall on the Amazon, making the supply of phosphorus to the watershed sustainable. Scientific observation helps draw a grand picture that the biodiversity of the Amazon is kept sustainable thanks to the African Sahara that is linked to the watershed through a water related air current.

As I have shown, water is closely associated with the hydrosphere, the atmosphere and the geosphere. Water is literally the foundation of prosperity of all living things on the earth. I expect that science and technology will further contribute to human prosperity through water.


6.Climate change and water related disasters

You may now understand that this delicate global heat balance caused by water sustains human life and prosperity on the planet. This balance, however, is now at grave risks. Why? Because of global warming and climate change.

The impact of climate change can initially be felt through water related disasters caused by extremely heavy rains, floods and droughts. These graphs show the trends of frequency of extreme rains in Germany, the US and Japan (Fig.12). They all show increasing trends in recent decades. This shows the result of a simulation of climate change in global rainfall intensity in accordance with the increase in carbon dioxide concentration (Fig.13). It is estimated that intensified rainfall will become more concentrated over a smaller area if carbon dioxide keeps increasing. This is a simulated case from India (Fig.14). Increase in carbon dioxide concentration is estimated to cause severer droughts in India.

Water related disasters may appear to be localized events which at a glance occur in specific regions or rivers. Scientific analysis, however, indicates that climate change is an underlying cause of their frequent occurrence. Severe damage is feared to increase exponentially if we do nothing now. In a few days or even hours, water related disasters will wipe away the fruits of development efforts over generations. The international community should unite to counter the natural threats that are occurring on a global scale.

7.Water to bring about prosperity, peace and happiness - towards achieving all of the Sustainable Development Goals -

Ladies and gentlemen,

The 2030 Agenda for Sustainable Development was adopted at the United Nations in 2015. Water related goals were agreed on as an independent SDG6. The issue of water-related disasters was addressed in Target 11.5. Water was positioned as a cross-cutting issue that connects major development goals such as poverty, education and gender. This, however, does not mean that these major development issues are automatically resolved when water related goals and targets are met. They will be resolved only if the cause-and-effect between water and other sectors are fully understood, sectionalism is overcome, and people of all sectors join hands to solve problems in comprehensive manners. For this, I call on people from the water sector to approach proactively and conduct dialogues with stakeholders of other major challenges such as gender, education, refugees and migration and poverty.

Water is a prerequisite for communities of people to live on quietly and peacefully. Women, children, elderly, people with disabilities and other socially vulnerable people suffer most by extreme water related disasters, droughts as well as regional instability. The international community needs to give priority to sustainable provision of water and sanitation even during emergencies.

I learned that in a variety of cases water has served as an agent for regional stability and cooperation. This is a result of endless efforts and the ingenuity of people over generations. We should learn from these good practices and experiences and take water action to help build prosperity, peace and happiness for the people.

The issue on water will be discussed intensively at the High Level Political Forum in the United Nations in July this year. I sincerely hope that this 8th World Water Forum will be an opportunity to deepen discussions and promote actions towards comprehensively solving major and urgent issues that the world is facing today.


I would like to conclude this keynote speech by expressing my sincere hopes as follows. The 21st century is said to be the Water Century. I hope this phrase will further evolve so that future generations may recall the 21st century as a century of prosperity, peace and happiness brought about by water. I would like to continue giving my full attention to this matter.

Muito obrigado pela atenção.(ムイント・オブリガード・ペラ・アテンサォン)