### Japan's History and Current Status of Water Resource Management (1950s–2020s)

### Japan's History and Current Status of Water Resource Management (1950s–2020s)

**1950s–Early 2000s: Foundation of Water Resource Development**
Water resource usage in Japan expanded significantly during the post-war economic growth period. To stabilize river flows, infrastructure such as dams and weirs were built primarily along the Tone River and Yodo River systems starting in the 1950s. This ensured stable water supplies for urban areas but raised issues like land subsidence due to groundwater extraction and pollution of rivers and lakes caused by industrialization.

**2010s: Advancement in Water Resource Management and Technological Innovation**
In the 2010s, the sustainable use of water resources became a critical issue. In agriculture, precision irrigation systems reduced groundwater usage by about 20% in Shizuoka's tea-producing regions. Meanwhile, industrial efforts saw companies like Sumitomo Chemical developing filters to purify industrial wastewater, achieving 90% reuse in Yokkaichi's industrial zones. Toray's reverse osmosis (RO) membranes were widely adopted in water treatment facilities domestically and internationally.

**2020s: Sustainable Water Utilization and Global Expansion**
By the 2020s, Japan's annual water resource usage reached approximately 78.5 billion cubic meters (14.8 billion for domestic use, 10.3 billion for industrial use, and 53.3 billion for agricultural use). Amid frequent droughts, improving water use efficiency has become a priority.
Companies like METAWATER Corporation have provided ceramic membrane filtration systems, widely adopted in Europe and Singapore. Toshiba Infrastructure Systems has launched wastewater treatment projects in the Ganges River basin in India, contributing to local water quality improvement.

In seawater desalination technology, Tsurumi Manufacturing has supplied high-performance pumps used extensively in the Middle East, including Saudi Arabia. Domestically, energy-efficient water treatment facilities have become widespread, with the Ministry of Land, Infrastructure, Transport, and Tourism promoting decarbonization in the sewage sector.

**Future Outlook**
The global water treatment market is expected to reach 100 trillion yen by 2025. Japan's technologies are gaining increasing importance in international markets, contributing to sustainable water management and global challenges.