The Future Washing Initiative held its 7th seminar “Future of Washing – From the Perspective of Household Wastewater” on April 12, 2023. More than 60 people, including the private sector and researchers, attended the event. Under the general chairmanship of Ms. Rieko Yamamoto from the Center for Environmental and Health Sciences at Hokkaido University, the participants have discussed the global situation surrounding water use from the following viewpoints: water supply and wastewater, community-based water supply and management in low- and middle-income countries, and small-scale distributed water cycle systems to solve the global water scarcity.

First, Dr. Fumiko Kasuga, the Director of Future Earth Japan Hub, explained the background and purpose of the Future Washing Initiative’s establishment and its activities to date. She emphasized the importance of considering “sustainable washing” while taking into account various aspects, including environmental and technological aspects (water and energy use), social aspects (declining birthrate and aging population), as well as cultural aspects (differences in hygiene awareness and laundry conditions in different countries and gender), and the seminars held to date. She also introduced the perspective of “household wastewater,” which was the theme of this seminar, while relating it to the United Nations’ Sustainable Development Goals (SDGs).

Next, Mr. Junji Hashimoto, Visiting Professor at Musashino University, Representative of Aqua Sphere Water Education Institute, gave a lecture on the theme of “Re-thinking Water Supply and Wastewater”. First, focusing on data from the Tokyo Metropolitan Government, he explained that we use about 200 liters of water per day to live, and treat it as wastewater. He also explained the drastic changes in human history of water use (human activities), from fetching water by human power, to  using gravity (waterways, etc.), and then to using energy to move water against gravity during the Industrial Revolution, adding how technological innovations have increased the amount of water used and the amount of wastewater. Next, regarding wastewater, he focused on the cholera epidemic during the Industrial Revolution in England, noting that the outbreak subsided as water and sewage infrastructure and other sanitation facilities were put in place. In addition, he highlighted the cholera epidemic in Japan during the Meiji era and the birth of sewage treatment facilities. He explained that the expansion of sewage facilities was behind that of drinking water facilities, and that many farmers used human waste as fertilizer and were unaware of the importance of sewage treatment.  In addition, he discussed the water pollution in the Sumida River and the development of sewage systems in line with factory effluent regulations in Tokyo during the period of rapid economic growth of the mid-1950s to mid-1960s. He explained that since then, our country has developed a sewerage system, and now the aging of the water and sewage systems has become a problem to be addressed. He then described the water situation in the world and its impact on people in low- and middle-income countries who lack access to safe and clean water and the infrastructure to supply and treat it. He also explained the declining awareness in Japan of each household’s commitment to “environmental considerations for sewage systems” and the impact of wastewater runoff (E. coli and microplastics exceeding the standard values at the Olympic and Paralympic venues). In addition, he stated that it is important to “ensure a healthy local water cycle” in terms of wastewater reuse, i.e., what kind of water is being discharged, in the future washing. Finally, regarding the relationship between water and humans, he focused on the “positive” impact of water on the human mental realm (the human mind) beyond its physical aspects, and touched on the importance of “wastewater” as well as water supply in terms of what kind of water flow is good for living organisms.

Next, Dr. Mayu Ikemi, Professor and Head of Department of Tourism Business, Faculty of Tourism, Sapporo International University, gave a lecture titled “Water Situation in Developing Countries and People’s Practices for Local Challenges: A Case Study in a Sub-Saharan African Village. The presentation introduced the global situation in which, as of 2015, approximately 90% of the world’s population had access to safe drinking water, but in low- and middle-income countries, especially in sub-Saharan Africa, 68%, or “one in three,” still do not have access, and there is also a disparity between urban and rural areas. She explained that water and sanitation are crucial to people’s lives, and in particular, the issue of supplying and securing water resources and safe drinking water involves a variety of “stakeholders” including local residents, citizen groups, government organizations, and private companies. She explained that countries, regions, and residential settings differ in terms of lifestyle, socio-cultural contexts such as religion and ethnicity, as well as income and access to systems and services such as education and health. In this regard, she stated that it is important to understand what benefits and advantages stakeholders can acquire and what innovations and measures they take to address water and sanitation issues, based on the characteristics of their communities. She explained that in Senegal, water supply is a top priority, however, there is a large disparity in its access between urban and rural areas. She added that in rural areas, government efforts and the mutual aid and self-help efforts of local residents have led to the installation of water systems in almost all households, greatly reducing the labor required to fetch water. However, they reported that water supply is unstable due to water outages and distance to water sources, and that tap water is not suitable for drinking because of the high concentration of fluorine in it, contributing to the fact that they use unhygienic well water as drinking water. She described how one village had water but did not have the proper equipment to pump it, and how they had installed modern equipment but were affected by breakdowns and maintenance problems. In the example of the residents’ organization, only some of the residents (village chiefs and their families) participated with low motivation (“debt” and “expectation” of benefits) due to personal factors. In contrast, she explained that in the more successful rural villages, the self-help efforts of the residents in setting and adhering to rules were a key factor. In conclusion, she stated that key factors such as overcoming the problem through self-help efforts without relying on others (e.g., government), information sharing with transparency, and individual residents’ organizations possessing (fulfilling) the necessary elements for group activities such as collaboration, solidarity, and sense of ownership, good relationships with stakeholders, and the selection of appropriate stakeholders to respect the initiative and autonomy of residents will lead to the resolution of water issues to be tackled by local communities.

Lastly, Mr. Yosuke Maeda, CEO of WOTA Corporation, gave a lecture on the theme of “Solving the World’s Water Problems with ‘Small-Scale Decentralized Water Recycling System. First, he mentioned his personal background that led him to work on solving water issues as the theme of this lecture, by describing various triggers such as small-scale water systems in his hometown, disasters he has seen and has heard about (the Teshima Island Incident, the Great East Japan Earthquake), and the current situation in urban slums around the world (Kibera Slum, Kenya). As a project currently being undertaken to address water issues during disasters (e.g., earthquakes in Japan and the Earthquake in Turkey and Syria), he explained about a water circulation system that enables the use of safe and clean water by collecting wastewater and treating it, a technology to recycle water in a compact, highly efficient, and safe manner through automatic control of water treatment considering water issues. He also stated that for developed countries, such as Japan, which have introduced water supply and sewage systems earlier than the other countries, it is necessary to replace inexpensive small-scale decentralized systems with large-scale centralized systems because of aging water infrastructure and the financial challenges due to a declining population in renewing and reconstructing pipelines. As a pilot, he stated that the company has succeeded in introducing completely off-grid housing (98% recycled and circulated use of household wastewater + 2% supplemented by rainwater), a residential water circulation system that is not connected to water or sewage systems, and that in Japan they are working to demonstrate this system in Futtsu City, Chiba Prefecture and throughout Ehime Prefecture. The project has been highly evaluated worldwide, including by the British Royal Family, and has led to an agreement for a public housing development project in Antigua and Barbuda, which is faced with severe water shortages. The project is planned to be further expanded to Palau, Saudi Arabia, the west coast of the United States, and other countries and regions suffering from similar water shortages. Finally, he explained the complex factors of the water problem, consisting of water shortage, water pollution, and water supply finances. The international trend is that waterworks development precedes sewerage development. Even in Japan, which has achieved both waterworks and sewerage development in the three stages of waterworks and sewerage development, there are various problems such as increased use of water resources development due to increased water consumption, over-investment in waterworks deployment and piping due to decreased water consumption and population decline, and damage to water supply infrastructure due to disasters. He also added that the company will continue to strive on working on the construction of small-scale decentralized systems by reusing rainwater and household wastewater as a universal approach to water solutions, regardless of different environments and conditions across regions and countries.

A panel discussion based on the above three presentations facilitated by Dr. Yohei Kaneko of Kao Corporation followed. The panelists included three speakers and Mr. Tomohiro Hirose of the University of Tokyo’s Faculty of Agriculture. First, Dr. Kaneko listed the take home messages for each of the speakers on their respective topics.

Next, Mr. Hirose asked Mr. Hashimoto about measures to address the aging sewer system and declining interest in water use in Japan. Mr. Hashimoto stated that it is important to use both large-scale centralized systems and small-scale decentralized systems, and that it is important for local residents to be actively involved in the process, which will enhance their knowledge of water issues.

Mr. Hirose asked Dr. Ikemi if there were any points that Japan should pay attention to in providing assistance, although the local context for solving water problems differs from region to region and country to country, and external intervention is not always successful. Dr. Ikemi responded that some people say it is better not to have outside intervention, but there is a risk that this will lead to a top-down approach (decision-making) by only local influential people, and that this may be necessary to some extent in order to prevent this.

Mr. Hirose asked Mr. Maeda if it is necessary to use not completely purified water, such as slightly lower quality water for agricultural use. Mr. Maeda replied that it is possible, but the quality of the water is quite different compared to household wastewater. He responded that the focus is first on solving household wastewater.

Dr. Kaneko then asked Dr. Ikemi to give examples of successes and failures in each village, although the context of each region in his lecture was different and the response to water issues varied widely. Dr. Ikemi noted that water issues are more actively addressed in villages where local leadership can be demonstrated, and that the local context of diverse ethnic groups and cultures is relevant to these efforts. In this regard, Mr. Maeda pointed out that it is important to spread water treatment systems in a manufacturing-industrial manner (automation) and to create a system that is tailored to local conditions through actual on-site human interaction, using the example of the Maasai people in Kenya, who use smartphones (technology) but also pump water manually (manual labor). The importance of creating a system that is attuned to local conditions through actual on-the-ground human interaction was also pointed out.

As the next theme, Dr. Kaneko asked the speakers if there were any examples of successful solutions to water problems in the region or initiatives to solve such problems. In this regard, Mr. Hashimoto explained that each company perceives issues differently when focusing on washing, and that there are responses based on the nature of the issue, using the example of cooperation between municipalities in upstream and downstream. Dr. Ikemi explained about the ingenuity of the Senegalese people regarding the quantity and quality of water, who are willing to spare no expense for drinking water for their health, even if they are poor. Mr. Maeda explained that the amount of water that can be reclaimed in water reclamation needs to consider the function of microorganisms that purify a certain volume over a certain amount of time (purification capacity), and that automating the management of biological treatment may bring about significant changes in people’s water use.

Next, regarding Kaneko’s suggestion that it is important not only to expand water infrastructure but also to change people’s “awareness” of water, Mr. Hashimoto stated that in addition to improving water infrastructure, it will be necessary to introduce small-scale decentralized systems and build automatic water systems in the future. In order to do so, it is important for each of us to share our awareness of the value of water (the cost of water supply, water demand, and infrastructure expansion). Mr. Maeda stated that if we are to establish awareness of the value of water, it is necessary to make the process “interactive” (e.g., visualizing the workings of people and things involved in water treatment to raise awareness and motivation) rather than one-directional (education).

A question-and-answer session with the audience followed next. In response to the question, “The wastewater from the washing process contains detergents such as surfactants and other contaminants, but are there any issues to be addressed in the regeneration process? He also answered that the cost of reverse osmosis membranes and the cost of water use could be reduced by reducing the amount of surfactants attached to reverse osmosis membranes and reducing their molecular level to a level where they can be degraded by microorganisms. He added that the amount of surfactant could be reduced by processing the object (such as the surface of a dish) to be washed.

Dr. Taro Yamauchi, Director of the Center for Environmental Health Science Research and Education at Hokkaido University and Professor at the Faculty of Health Sciences, asked Mr. Hashimoto about the relationship between the “meaning of water” and aspects such as ethnicity and culture. In regard to this, Mr. Hashimoto stated that in a country characterized by diverse watersheds, the organisms that inhabit them are also diverse, which fosters multi-faceted cultures (spheres) in each region, and that it is necessary to construct methods and approaches for water treatment that are tailored to the context of each region. Prof. Yamauchi then asked Mr. Maeda about the possibility of applying off-grid housing in urban slums with poor water and sanitary conditions and his approach. Mr. Maeda explained that India is working on the installation of inexpensive public sanitation toilets (flush toilets) that do not require water supply and sewerage system.

At the end of the seminar, Dr. Kaneko stated the importance of considering the context of each region, thinking about the use of water in a cycle, changing the awareness of the value of water among individual water users, and visualizing the people and things related to water. The speakers included Mr. Hashimoto, who talked about the relationship between water as a solvent and people, Dr. Ikemi, who talked about the essence of “washing” and “cleanliness” (how it affects people), Mr. Maeda, who talked about the different cultures of washing and water use in each region that are related not only to material cleanliness but also to the spiritual cleanliness, and the importance of taking individual experiences into consideration as a starting point for improving people’s lives and society. Finally, Mr. Hirose commented that people in different regions have different ideas about water and that visualization of the problem, in addition to awareness of the current status of water, can be a driving force for individual behavior change.