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Is water of Yokohama somewhere and others?

Last update date December 28, 2018

Where does water of Yokohama come from?

Water source of Yokohama is 5 systems of the Doshi River, Sagamiko, Banyu River, company group Sakawa River, company group Sagami River.
After cleaning in method of water purification called rapid filtration method (in Kawai film filtration method) at water purification plant of three city of Kawai, Nishiya, willow tit and four water purification plant of wide area Channel company corps (※) in Kanagawa, and performing water quality test, and having confirmed security, water of these 5 systems is saved in distributing reservoir of 22 city. We send from there to house of everybody with water pipe.

Water source of Yokohama-shi
The nameDaily water intake quantityWhat water is it?Where do you go?
The Doshi River system172,800 cubic metersWater of the Doshi RiverTo Kawai water purification plant
Sagamiko system394,000 cubic metersWater which we saved in SagamikoTo Nishiya water purification plant
Banyu River system284,700 cubic metersWater which had enough being Lake Tsukui mainlyTo willow tit water purification plant
Company group Sakawa River system605,200 cubic metersWater which had enough being Lake Tanzawa mainlyTo water purification plant of wide area Channel company group (※) in Kanagawa
Company group Sagami River system499,000 cubic metersWater which had enough being Lake Miyagase mainlyTo water purification plant and willow tit water purification plant of wide area Channel company group in Kanagawa

(※) Yokohama-shi, Kawasaki-shi, Yokosuka-shi, Kanagawa is public, and wide area Channel company group in Kanagawa invests and it produces tap water and sells to investment 4 group.

When was water supply of Yokohama done?

Modern channel of Yokohama was completed for the first time in Japan in 1887 (Meiji 20) 130 years ago.
Modern water supply is water supply which is using currently which pressures with water pipe of iron, and sends water which we cleaned by filtration to faucet.
Population of Yokohama rapidly increased after port was opened in 1859 (Ansei 6), but, only with water which was salty even if a lot of places that filled up the sea and marsh dug well, lacked drinking water.
Therefore we asked Henry Spenser Palmer of British engineer for plan of Yokohama Channel and constructed for two years six months and completed modern times Channel.

Environment of water source?

"Way will forest at the head of a river" of Yokohama-shi is in one, Doshi-mura, Yamanashi of water source of Yokohama.
We purchased the forest of Doshi-mura from Yamanashi in 1916 (Taisho 5) to follow the quality of the water of "the Doshi River" which was one of the precious water sources of Yokohama-shi. We own forest at the head of a river of 2,873 hectares equal to about a one-third of Doshi-mura and are managing now. In forest at the head of a river, "we save water" is said to have three roles (water source cultivation function), "we purify water" "relaxes flood".

What kind of activity do you carry out to protect forest at the head of a river?

The forest which Yokohama-shi owns maintains "we save water" premeditatedly so that three roles of water source cultivation to "relax flood" can serve as "we purify water".
On the other hand, volunteer groups of Yokohama-shi where Water Works Bureau called push forward the forest maintenance such as thinning as the forest which is not well-kept increases, and forest under private ownership of Doshi-mura has decreased water source cultivation function.

Even citizen's all of you who could not participate in volunteer activity directly installed fund to be able to participate in water source maintenance activity in form called fund cooperation widely.
As for this fund, it is from contribution from all of citizen, company, the groups and a part of sales of plastic bottle "true children The Water".

Inquiry about water supply to Water Works Bureau customer Service Center

Water Works Bureau customer Service Center

Telephone: 045-847-6262 fax: 045-848-4281
※You run, and please be careful not to make any mistake

Inquiry to this page

Water Works Bureau General Affairs Department General Affairs Division

Telephone: 045-671-3105

Telephone: 045-671-3105

Fax: 045-212-1155

E-Mail address [email protected]

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