Imagine a household that takes 100 showers’ worth of water out of its own wastewater in a single month. That is roughly what a Japanese company says happened in a demonstration home in Antigua and Barbuda, and it is now using the result to argue for a different way to supply water on islands.
On November 3, 2026, WOTA, a Tokyo-based water technology company and Earthshot Prize finalist, issued a news release timed to the Commonwealth Business Forum 2026, held November 2 to 4. In it, WOTA presents home water regeneration as a route to growth for water-scarce Caribbean islands rather than only a way to cope with climate shocks.
How the WOTA Unit works
According to WOTA, the WOTA Unit is a small residential water regeneration system. It takes wastewater from kitchens, bathrooms and laundry and treats it so the water can be used again at home. WOTA says it can regenerate up to 97% of that wastewater, though it notes the recycling rate may vary with the usage environment and how water is used.
The company describes the control side as automated. Sensors continuously monitor water quality and operating conditions, while algorithms control the treatment without a person adjusting it. WOTA calls this its autonomous water treatment control technology, and says it has worked on decentralized water regeneration systems since its founding in 2014.
What the Antigua demonstration showed
WOTA is working with communities in Antigua and Barbuda, in collaboration with the island nation’s government. The project is supported by Japan’s Ministry of Economy, Trade and Industry through the United Nations Industrial Development Organization (UNIDO).
The headline number comes from one household. In a single month, the system regenerated 1,720 of the 2,356 US gallons the household used, which WOTA equates to 100 showers. That reduced the household’s need for additional freshwater by 73%.
WOTA is careful about the limits of this figure. It says the result reflects a single household over one month and is not a measure of island-wide impact, and that the wider effect will depend on the scale and conditions of deployment. That caveat matters: a promising pilot is not yet proof that the approach works across a whole island.
Why islands are a pressure test
The release lays out why small islands face a tough water problem. Limited land means limited freshwater, while population growth and tourism keep raising demand. WOTA cites the Food and Agriculture Organization of the United Nations, which classifies Antigua and Barbuda and Barbados as water-scarce countries. It also says Antigua and Barbuda has around 557 cubic meters of renewable water per person per year, well under the 1,000 cubic meter scarcity threshold.
Antigua and Barbuda has strengthened its supply, the release says, but still faces structural pressure. Its largest reservoir can run dry during parts of the year, desalination is costly and energy-intensive, and wastewater can reach the waterways and beaches the island economy relies on. WOTA also points to a warning from the Caribbean Institute for Meteorology and Hydrology that below-normal rainfall is expected across much of the region into early 2027.
A different path to growth
WOTA’s argument is that islands can build water reuse in from the start. Because each unit regenerates water where it is used, capacity can be added household by household and community by community, without waiting for large networks to be built. Working alongside conventional networks, the company says, decentralized regeneration can make better use of limited water, help keep essential services running during disruption, and reduce the wastewater that reaches the sea, which helps protect coral reefs, beaches and tourism.
WOTA’s CEO, Yosuke Maeda, said water should be what makes island growth possible rather than what holds it back. Antigua and Barbuda’s Prime Minister, Gaston Browne, said he believes the technology will bring some resolution to the island’s water shortage and that the government fully supports it. A resident taking part in the demonstration, Kevin Joseph, said the main benefit is a consistent supply of clean filtered water for every use in the home.
Building on the Antigua project, WOTA leads the Water 2040 Island Grows Initiative. Looking toward 2040, it aims to make small-scale, decentralized water regeneration part of everyday water supply on islands in the Caribbean and beyond, and it is seeking partners among governments, utilities, businesses and communities.
What it means
For utilities and planners, the idea is a modular complement to big infrastructure: add units as demand grows, and reduce both freshwater draw and wastewater discharge at the source. For households, the appeal is a steadier supply when reservoirs are low. For investors and officials, the open questions are the ones the release itself hints at: how results hold up across many homes and seasons, what units cost to buy and maintain, and how regulators treat reused household water. None of those answers are in the announcement, and the performance figures are company-reported.
The bottom line
WOTA’s Caribbean push turns one household’s month of data into a case for decentralized water reuse on islands. It is an early, single-site result, but it points to a practical idea worth watching as dry seasons lengthen: treat water where it is used, and use it more than once.