The WOTA Unit is the world's first household water circulation system that purifies up to 97% of domestic wastewater from bathrooms, kitchens, and laundry. It creates safe, reusable water, enabling a life free from conventional water and sewer networks. The system can be supplemented with rainwater or other sources, allowing for flexible implementation. This technology ensures water quality meets or exceeds WHO drinking water standards and all 51 parameters of Japanese tap water quality, providing a resilient solution for any region.

Developing decentralized water circulation systems and autonomous water treatment control technologies that recycle household wastewater for maximum reuse, tackling issues such as water scarcity, pollution, and uneven distribution, WOTA Corp. commit to solving the structural challenges of global water issues.

◆Clean water
"WOTA Unit" provides clean, safe water that meets WHO Guidelines for drinking-water quality. Say goodbye to concerns about bacteria, viruses, or harmful chemicals.
◆Water resilience
Even in times of drought or infrastructure failures, "WOTA Unit" can continue operating as long as electricity is available. This allows you to live independently of local water infrastructure issues.
◆Smart maintenance
You can monitor available water levels and receive maintenance notifications through the dedicated app. Managing your daily water supply has never been easier.

"WOTA Unit" is a decentralized water circulation system that purifies up to 97% of household wastewater—from bathrooms, kitchens, laundry, and other domestic uses—into safe, reusable water, enabling water reuse without connection to conventional water and sewerage networks.
By applying biological treatment that utilizes microorganisms to decompose organic matter in gray water, toilet wastewater, and rainwater, followed by membrane filtration and disinfection processes using deep ultraviolet light and chlorine, the system supplies clean water that meets the 51-item water quality standards stipulated by Japan’s Waterworks Act. However, for toilet flushing water quality, compliance is ensured according to the Ministry of Land, Infrastructure, Transport and Tourism’s "Manual on Water Quality Standards for Reuse of Treated Sewage Water."

The system is adaptable to various configurations, accommodating scenarios such as circulating both domestic water and toilet water, or circulating domestic water only. Maintenance notifications, including available water volume and filter replacement alerts, can be monitored via a dedicated app. The system remains operable during emergencies as long as a power source is available.

This solution is being implemented as a complementary water supply and wastewater treatment method to conventional water and sewage infrastructure in depopulated and remote island regions across Japan, as well as in island nations in the Caribbean, such as Antigua and Barbuda.

• Japan
• Central/South America

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• 6. Clean Water and Sanitation
• 7. Affordable and Clean Energy