Even if water and sewage systems achieved 100% global coverage, water issues would not be fundamentally resolved.

The human body requires approximately 2 liters of drinking water per day. In todays world, each person uses roughly 200 liters of water per day. We have water supply to provide safe water for use when needed, and wastewater treatment to purify used water. To meet the demands, humanity has been pushing for the spread of water supply and sewage systems.

However, due to rapid population growth and climate change, water concerns have risen in recent years; the operation of existing water supply and sanitation systems is insufficient. According to the United Nations, current water resources will only be able to meet 60% of projected demand in 2030; by 2050, half of the worlds major cities (i.e. New York, Shanghai, Delhi, Sāo Paulo) will be water stressed, with up to 5 billion people lacking adequate access to water for at least one month per year. Water challenges are no longer limited to select places; countries at various economic stages face diverse water challenges, making it unrealistic to rely solely on water and sewage systems to provide solutions.

Solving one challenge gives rise to the next: the complex issue of water problems

Water scarcity

Inadequate water sources and supply facilities prevent local people from accessing sufficient safe water for domestic use.

Water supply

Water pollution

Domestic wastewater is not properly treated, contaminating precious water resources such as rivers and groundwater.


Deterioration of water supply finances

Maintenance costs of water treatment facilities and pipeline networks increase, putting pressure on national and regional finances.

Although water supply systems can help in tackling water shortages, it cannot prevent contamination of water resources by wastewater. Conversely, sewerage systems can address pollution, but will cause significant financial burdens due to long-term maintenance costs. These financial challenges are particularly pronounced in advanced nations that have achieved economic maturity and are experiencing population decline, as it is harder to maintain water and sewage systems in sparsely-populated areas with inefficient piping networks. Even in large cities with efficient networks, water scarcity is on the rise due to population growth and the impacts of climate change.

In this way, developing water supply and sewage systems demands significant time and money, often revealing a structural complexity where solving one problem exacerbates another. Traditional water supply and sewage infrastructure cannot create a world where safe water is readily available without burdening the environment or future generations. Therefore, there is a critical need for innovative technology and solutions capable of solving a variety of water-related challenges.

Instantly turning used water into usable water: Small-scale water recycling systems

To address this challenge facing humanity, WOTA focuses on water recycling. Traditional water infrastructure follows a use and dispose model where water is drawn from natural sources and treated wastewater is discharged into rivers or seas. In contrast, we have created a cyclical model where wastewater is reimagined as the most accessible water source and is recycled on-site for repeated domestic use. We are developing an innovative household system called a small-scale decentralized water recycling system, which makes the seemingly impossible feat of water recycling at the household level a reality, using our core technology driven by autonomous water treatment controlled by sensors and data science.

Transforming society by starting with solving local water issues: small -scale decentralized water infrastructure


Modern society has aimed to be a large-scale centralized water consumption society, where all houses are connected to a centralized water and sewage network that draws water from natural sources and processes and disposes of it after one use. Conversely, WOTA aims to create a small-scale decentralized water recycling society ensuring both environmental and financial sustainability by repeatedly reusing a limited water supply within each household.

Having a small-scale decentralized water recycling system at home frees individuals from the risk of water shortages, by converting wastewater into domestic water. This system collects all household wastewater, eliminating concerns about polluting rivers and seas. Even in cases of water supply disruption due to disasters, individuals can continue to use water without worry.

If more people recycle water like this, the need for costly and extensive pipeline networks diminishes. This reduces the financial burden on water utilities, facilitating investments for the future, in areas such as education, welfare, and the environment. In this way, the small-scale decentralized water circulation system addresses water challenges at the household and community levels, and ultimately has the potential to resolve the fundamental water issue facing modern society.

To achieve a future where nobody faces water scarcity, WOTA is accelerating the development and implementation of this new water infrastructure technology.

Demonstration of small-scale decentralized water recycling systems in addressing water problems.

WOTA is accelerating the development and implementation of small-scale decentralized water recycling systems through collaborative trials with government and local authorities.

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