A type of self-pumping water, called uchinuki, permeates through the surrounding land and is widely distributed throughout old Saijo City. It is said that there are approximately 2000 water zones.
In old days, people obtained this ground water by using their strength to ram an iron bar into the earth, making a long hole. Then they rammed in bamboo tubes without joints into the holes. This method had been passed on from the mid-Edo Period (1700s) to around 1945.
Today, the head of iron pipe is processed to make the same kind of hole. This pipe is rammed in using air hammers and compressors to hit the ground water zone, thus obtaining ground water. The quantity of flowing water obtained by uchinuki runs up to approximately 90,000m3 a day, and is used widely as water for living, agricultural, and industrial use, taking advantage of its stability in temperature throughout the four seasons. The water obtained through uchinuki is selected as one of the 100 famous spring waters throughout Japan.

The purpose of the 100 famous spring waters is to rediscover the excellence of the pure water throughout Japan, widely introducing the findings to the public to raise their consciousness with respect to water. At the same time, this also aims to have the public gain an appreciation of water preservation as well as to actively protect high quality water sources and our water environment. The former Environmental Agency made this selection in January of 1985. There are 100 famous selected spring waters throughout Japan. Including uchinuki, three are from Ehime Prefecture.

In many cases, famous spring water is used as drinking water and taken as a synonym for delicious water. However, not all famous spring water is delicious water. Delicious water should go down the throat smoothly and be safe to drink.
"Uchinuki" goes beyond being a selected spring water to also be safe and delicious water, which is the best possible water for drinking water.