No. 109: Water business in Japan and the world (28) (November 1, 2011)

Building a society that does not waste water

Water is a finite resource. In order to prepare for the decreased safety of water utilization caused by climate change, we need to build a society that does not waste water. Climate change causes not only a drought but also a flood as we see in the ongoing disaster in Thailand. If we set water in water reservoir and underground water apart for later use by virtue of effective utilization of rainwater and reclaimed water, we can secure stable water supply even in a drought. Tokyo uses 426 cubic meters every day that is equivalent to 3.4 times bigger than the volume of a Tokyo Dome. About 70% of the 426 cubic meters is daily life water at households.

The water amount from the tap is 12 liters per minute, and you can reduce the amount to 5 liters if you use a cup when you brush your teeth. If you use a bucket instead of running water when you wash you car, you can reduce the water amount by 210 liters. Washing dishes by hands needs only one tenth of water amount needed by a dishwasher. If you wash dishes by your hands after three meals a day, you can economize as much as 300 liters a day. Demand for water-saving apparatus has been growing lately.

According to a questionnaire survey conducted the government, 39% of the respondents wish to buy a water-saving toilet system, 25% express the desire to buy a water-saving washer, and 19% think about introducing equipment of rainwater utilization. Flushing toilet has the larges share of 28% of water consumption in a household. It is followed by bath that accounts for 24%, cooking 23%, and laundry 17%. A Tokyoite uses about 240 liters of water in a day. It is possible to reduce water consumption greatly by using water-saving equipment and learning the behavior to economize water.

Japan can take pride in the state-of-the-art membrane technology and the management of water leakage. Besides, Japan can spread its traditional rules and customs for water saving worldwide. For example, water sprinkling on the road is one of Japan’s traditions to cool down the street. Whatever measures are taken, the attitude and behavior of each person are the strong weaponry for effective and efficient usage of water. (The end)