Sewerage in Kobe

Kobe is the 7th-largest city in Japan with a population of approximately 1.52 million people as of 2019.
In Kobe city, domestic wastewater is treated through the public sewerage system and six WWTPs, which serve 98.7% of the population [over 1.52 million residents as of end of fiscal year (FY) 2019].

History of Sewerage Development in Kobe

Following the establishment of the Act on Construction of Kobe as an International Port City in 1950, the construction of Kobe's first sewerage project began in 1951. During the period of high economic growth in 1960s, Japan experienced some serious environmental pollution problems. To preserve water environments and implement fundamental solutions to exacerbating water pollution, the Water Pollution Control Law was enacted, and the Sewerage Law was revised in 1970.
In Kobe, we focused on investing in sewerage construction in 1970s, aiming for 100% installation rate of flush toilets.

History
1951	Modern sewerage projects began Constructed separate sewerage system (in which sanitary sewage and stormwater are collected in separated sewers)
1958	The first modern sewerage treatment plant in Kobe begins operation （CHUBU STP）
1970	Focused investment for sewerage construction
1990	Water reuse projects began
1995	Great Hanshin-Awaji Earthquake (Higashinada STP was closed)
2001	Reclaimed wastewater supply began
2008	Automobile fuel project using KOBE Biogas began
2010	Kobe Biogas injected into city gas mains International contribution project began
2011	Sewerage network system began operation
2012	KOBE designated as "Water environment solution Hub"
2013	Digestive sludge phosphorus recovery verification project began

Separate sewer system

Kobe's sewerage has used a "separate sewer system" which use different pipes for rainwater runoff and sanitary sewage, since its beginning, aiming for the effective utilization of resources and the improvement of water environment. Sanitary sewage is sent to water reclamation centers and stormwater is discharged directly to rivers and into the sea.

Facilities of the Sewerage

Generally, all treatment plants and pumping stations are built on sites near the coasts.

Sewers	Sewers transport sewage to waste water treatment centers. They are also referred to as "Sewer pipes".
Pumping Stations	Pumping stations are used in bringing sewage to the waste water treatment plant.
6 Wastewater Treatment Plants (WWTPs)	Waste water treatment plants have two major functions, treatment of sewage and sludge generated as a result of the treatment of sewage.

Kobe Biogas

Various usages of Resources obtained from sewage

Treated water, sludge and heat energy are produced by sewage treatment plants.
Our promotion of effective utilization of these resources helps to control the production of greenhouse gas, and contributes to an environmentally friendly city that effectively utilize waste products.

25 Years after the Great Hanshin-Awaji Earthquake

Vehicle fuel		City gas pipe injection
Gas Station Filling volume:2,700 m3 per day Number of units:7,115 units		City gas production facility Injection quantity: 1,070,000 m3 per year (Equivalent to 2,000 households)
Co-power-generation		Use of local biomass for sludge treatment efficiency improvement and biogas increase
Power generation by digestion gas Power generation volume: 10,000 m3 per day		Facility accepting biomass

Water Reuse

In Kobe, reusing of treated wastewater for water trucks, landscaping, car washing or flushing toilets is widely used. Water reuse can be an option for making a contribution to Low Carbon Society.

Use of Recycled Water

Water trucks		Landscaping
Car Washing		Flushing toilets

Kobe City Flood Hazard Map

Kobe City Flood Hazard Map is a map that provides risks and evacuation information in case the river overflows, or in case there is rainwater flooding (urban-type flooding) due to typhoons, heavy rainfalls or the like. It is available in four languages: Japanese, English, Chinese, and Korean.

Great Hanshin-Awaji Earthquake

Water works and sewage facilities have been affected heavily by the earthquake. In particular, the largest wastewater treatment plant 'Higashinada WWTP' completely hadn’t woked for 100 days.

Sewerage Network System

Based on lessons from the Great Hanshin-Awaji Earthquake, the city connected 4 treatment plants via deep underground large-diameter shielded pipes (total length: approx. 33 km). This forms a sewerage network system that will continue to operate even during a disaster.

>>read more（Sewerage Network System）