Ariake Water Reclamation Center
Ariake Water Reclamation Center is a separate sewage system water treatment facility. It is built in Tokyo maritime sub-city center's Clean Center. Its treatment area is part of the Sunamachi Treatment District（Tokyo maritime sub-city center and surrounding areas, and part of the landfill inside the central breakwater）.
The Center adopts advanced wastewater treatment using A2O method（anaerobic-anoxic-oxic process）and biological filtration process, and discharges the treated water into Tokyo Bay（Ariake-nishi Canal）. A part of the treated water is further cleaned using ozone before being used inside the Center for cleaning facilities, cooling machines, and is also used as water for flushing toilets in buildings in Tokyo maritime sub-city center.
The generated sludge is pumped through pressure pipelines to Tobu sludge plant for treatment.
（As of April, 2020）
|General data of the facility||Operation started||September 1995|
|Water treatment facilities||Grit chambers||2|
|Primary sedimentation tanks||3|
|Secondary sedimentation tanks||3|
|Biofilm filtration tanks||6|
Average quality of intake and discharge water
The final effluent form the water reclamation center complies completely with the water quality standards of the Tokyo Metropolitan Environmental Security Ordinance and is sufficiently clean for fish to live in.
|Item||Influent||Final effluent||Regional water quality standards|
|COD(Mn)||100||9||15 or bellow|
|Total nitrogen||45.6||8.7||20 or bellow|
|Total phosphorus||4.7||0.2||1.0 or bellow|
※ The higher values of BOD and COD indicate the higher levels of water contamination. BOD describes the amount of oxygen required by microorganisms to eat organic material in water, and COD describes the amount of oxygen required by oxidizer to decompose organic material in water. The quality levels of discharged water are specified in terms of BOD for rivers and COD for seas. Total nitrogen and total phosphorus are closely related to the generation of red tides.
The sewerage system is principally made up of 3 facilities.
Sewers, which collect and carry sewage.
Pumping stations, where sewage is pumped up so that the sewers do not get too deep.
Water reclamation centers, where sewage is treated to be clean water.
Inspections, cleaning, and repairs are done daily in order to make sure each of these facilities works properly.
The Role of Tokyo Sewerage Systems
Improvement of Living Environment through Sewage Treatment
Sewage discharged from homes and factories is treated to ensure a comfortable living environment.
Preventing Flooding through the Removal of Rainwater
The city is protected from flooding through the speedy drainage of stormwater which falls on land surface.
Protecting the Global Environment
We treat sewage and release cleaned water, to carefully protect the water quality of rivers and the sea. We also recycle treated water and sludge, and utilize unused energy, as we work to build a recycling city.
Features of Ariake Water Reclamation Center
Advanced Wastewater Treatment Facility（A2O method）
Because of nitrogen and phosphorus hard to get removed by means of the wastewater treatment so far used, the red tides still appear in Tokyo Bay due to eutrophication. Hence, we are adopting an advanced wastewater treatment called A2O method（anaerobic-anoxic-oxic process）in order to remove larger amount of nitrogen and phosphorus.
Wastewater and activated sludge are mixed here without air supply. Due to the lack of oxygen, the microorganisms in the activated sludge discharge the phosphorus that they have stored within themselves into the water.
The water from the aerobic tank containing nitrogen combined with oxygen is fed back to the water from the anaerobic tank. The microorganisms then take in the oxygen combined with the nitrogen and start breathing, while the nitrogen deprived of the oxygen gets released in the form of gas.
By blowing sufficient oxygen, the organic substance gets decomposed by microorganisms while nitrogen is combined with oxygen. Further, the microorganisms absorb more phosphorus than is released from the anaerobic tank.
Biological Filtration Method
The biological filtration facility has almost the same structure as the sand filtration facility, so that the suspended solids（SS）get removed through physical filtration. Further, air is passed through the bottom of the filter to create a film of aerobic microorganisms（biofilm）on the surface of the filter. This allows the biodegradable dissolved organics remaining in the raw water（treated wastewater using A2O method）to get adsorbed, dissolved and removed. In this way, cleaner treated water can be obtained.
Supply of Reclaimed Water to Tokyo Maritime Sub-city Center Area
Ariake Water Reclamation Center supplies a part of the advanced-treated water as the reclaimed water to Tokyo maritime sub-city center area. The reclaimed water is effectively used for flushing toilets in buildings and for washing the vehicles of "Yurikamome", new transport system running through Tokyo waterfront area.
Above-ground Space full of Sports Facilities
Most of the treatment facilities are installed underground, with the above-ground space used for gymnasiums, heated pools, and sport gyms of Koto-ward and Ariake Tennis Park. These facilities are used and enjoyed by a large number of people.
2-3-5 Ariake, Koto-ku, Tokyo 135-0063,
8-minute walk from Odaiba-kaihinkoen Station on Yurikamome Line (Tokyo Waterfront New Transit).
Tokyo Sewerage Museum "Rainbow"
There is a facility to enjoy the experience of learning about the sewerage system, its roles, and the importance of water environment.
- Hours:nine half o'clock to sixteen half o'clock
- Entry Fee:Free
- Closed Mondays（open on holiday Mondays, closed the next day）and the New Year's season
- Address:-3-5 Ariake, Koto-ku Ariake Water Reclamation Center Management office（A-tower）5th floor
- Website:Tokyo Sewerage Museum "Rainbow"
Tokyo Bureau of Sewerage
Tokyo Amesh is the system that shows rainfall in and around Tokyo in real time. The rainfall is measured by radars and ground rain gauges.
※ Tokyo Amesh is the registered trademark of the Tokyo Metropolitan Government.
Animation and video are used to allow people to experience the sewer system and wastewater treatment system in a fun way that would not be normally possible.
Beware of croocked dealer who pretend to be related to the Bureau of Sewerage!
The Bureau of Sewerage does not rely on businesses to repair or clean drainage facilities in housing.
Facility tours of Water Reclamation Centers
Facility tours of water reclamation centers are available except weekends, holidays, and the New Year's season.
Please contact us about reservations and details.