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- Overview of Nishiya Water Purification Plant Facilities
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Overview of Nishiya Water Purification Plant Facilities
Last updated on March 4, 2025.
Nishiya Water Purification Plant Nishiya Water Purification Plant
The Nishiya Water Purification Plant uses Sagamiko as its water source. Founded in 1915, the processing capacity at that time was 73,360 cubic meters per day. Following the completion of the eighth expansion work in 1980, the current processing capacity is 356,000 cubic meters per day (about 1.1 cups of Yokohama Stadium). The purified water is mainly supplied to Tsurumi, Kanagawa, West, Middle, South, and Hodogaya wards.
| Location | 522, Kawashimacho, Hodogaya-ku, Yokohama-shi |
|---|---|
| Site area | 151,668 square meters |
| Processing capacity | 356,000 cubic meters per day |
| Water source | Sagamiko |
| Processing method | Rapid filtration method |
| Sinking pond | Sidestream type (with slope plate) 4 ponds of 90,000 cubic meters per day |
| Filtration pond | The first rapid filtration pond has 10 ponds of 116 square meters, and the second rapid filtration pond has 16 ponds of 90 square meters. |
| Reservoir | Total effective water storage capacity 144,800 cubic meters |
| Wastewater treatment facilities | Processing capacity is 7,600 kilograms per day (dry weight) |
Nishiya water purification plant floor plan (it may be different from actual because it is under Nishiya redevelopment project.)
Treatment process of water treatment plants
1 Central Management Office
It is the heart of the water purification plant and operates and monitors all facilities 24 hours a day.
2 Arriving Mizui
The water taken by Sagamiko (raw water) is the first to arrive at the water purification plant. The amount of water is adjusted here and sent to the sinking pond.
3 Sinking Pond
Inject a flocculant (polyaluminum chloride) into the raw water. The suspended matter becomes a large lump (flock) and sinks.
4 filtration pond
Small suspended matter that was not removed in the sinking pond is removed through a layer of sand and gravel.
5 Reservoir
In a warehouse that stores tap water, the amount of water is adjusted according to the amount of water used and distributed to homes, schools, factories, etc. In addition, the upper part of the No. 3 reservoir is lent to Yokohama FC, a professional soccer team, as a soccer ground.
6 Washing tank
This aquarium stores water higher than the filtration pond and cleans the filtration pond using the momentum of the water flowing from above.
(Reservation capacity of 1,000 cubic meters)
7 Water Quality Meter
We monitor the quality of the finished water (purified water) from raw water for 24 hours in order to always send safe water.
8 Wastewater treatment facilities
The impurities removed in the sinking pond and filtration ponds are concentrated and separated into water and mud by a dehydrator.
9 Registered Cultural Properties
In June 1997, four reservoirs, one reservoir water purification Inoueya, and one reservoir reservoir water distribution Inoueya built in 1915 became registered cultural properties of the country.
10 Fresh drinking fountain
We have set up a drinking fountain so that visitors to the water purification plant can drink the freshly made water.
Overview of the Kawai Purification Plant Facility
Overview of the Kosuzume Purifiction Plant Facility
Inquiries to this page
Nishiya Water Purification Plant, Water Works Bureau Water Purification Department
Phone: 045-371-5335
Phone: 045-371-5335
Fax: 045-371-8969
E-Mail address [email protected]
Page ID: 189-490-609
