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Environmentally friendly water supply system

a. Priority of natural flow-down system and increased efficiency of pump system facilities

Together with giving priority to the purification amount of the natural flow-down system purification plant, the decreasing of the purification amount of pump system purification through purification plant restructuring/rearrangement, and attempting to reduce power consumption.

b. Use of new energies such as photovoltaic power generation, etc.

Together with promoting the installation of solar panels and small hydroelectric power generation facilities at purification plants, etc., the introduction of renewable energy, in cooperation with university research organizations perform investigation/research for the development of new energies.

Installation of Photovoltaic Facilities in Purification Plants

Solar Panels
Solar Panels

When installing
(1) Arched covers for the filtration basin to prevent foreign substances from getting in, and to restrain the amount of chlorine consumption,
(2) Light shielding plates for the sedimentation basin to prevent algal growth, and
(3) Covers for the distribution reservoir to prevent the odor generation, we installed the photovoltaic panels for the effective utilization of the top of such equipments, and use the generated natural energy for the operation/control of the Purification Plants.

Implementation of Small Hydraulic Power Generation

The small hydraulic power generation is implemented in Kohoku distribution reservoir by utilizing the surplus energy of the water pipelines. Generated power is supplied to the adjacent street lights and sold to the power company.

Small hydroelectric power generation image drawing

Countries and the number of participants
EquipmentPower generation capacity (kWh)Expected amount of power generation
Amount ofCO2 reduction(t-CO2)
Small hydraulic power production plant 300 1,800,000 765
Photovoltaic generation equipment 903 949,000 404
Total 1,203 2,749,000 1,169
(as of the end of fiscal year 2008)

c. Efforts towards an environment that makes use of water systems

Together with reducing power consumption through the promotion of 4-storied direct coupling direct pressure type water supply, attempting to reduce the environmental impact through the use of high efficiency activated carbon.

d. Water source maintenance through citizen cooperation

Utilizing the "Yokohama Water Birthplace Doshi-no-mori Fund," together with the promotion of watershed protection forest maintenance through citizen volunteers, utilizing the CO2 absorption authentication systems of Yamanashi Prefecture, we are involved in watershed protection forest maintenance by cooperating with businesses/groups.

e. Other efforts towards environmental preservation

- Introduction of government facility maintenance/power saving equipment that took the environment into consideration

Photocatalytic Curtain Wall Sprinkler System

Kikuna Water Plaza introduced the new technology (photocatalytic curtain wall sprinkler system) for the first time in the world. The technology is expected to reduce the cooling load by using water. The pipes are installed at the top of the window, and the system sprinkles water to the glass surface through the holes. The titanium oxide photocatalyst coating improves the water affinity with the glass surface, and water runs down, covering the surface with thin water film. At this time, water evaporates, draws heat, and reduces the cooling load. In the verification test, the glass surface temperature was lowered about 10°C, and the room temperature was lowered about 2-3°C. It was also observed that the heat island phenomenon in adjacent area was reduced due to the cold radiation from water film.

- Efforts towards environmental education

In order to improve a consideration of environmental preservation and our efforts, we promote various entertaining environmental studies and field trips.

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水道局噴水マーク Yokohama Waterworks Bureau, Human Resource Division - Created on 2011, 1, 20 - Updated on 2011, 1, 20
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