To promote sewage works intensively and systematically giving attention to
citizen's viewpoint for public works, watershed management,
cooperation with various organization, effective management of facilities, and
measures for internationalization.
1. Ensuring the Comfortable and Hygienic Life
Promotion of the construction of wastewater treatment systems, based on the appropriate selection of suitable wastewater treatment method for regional characteristic to eliminate the area where domestic wastewater is not treated.

Wastewater Treated Population Rate   76%(2002) 86%(2007)
Percent of population served by wastewater (gray and black water) treatment systems including sewerage systems, community sewerage treatment plant, household wastewater treatment tank, etc.
Note; In Japan, almost all black water in the area where wastewater treatment
       systems are not served, is transported to night soil treatment plant and
       treated.

Sewered Population Rate   65%(2002) 72%(2007)
Percent of population served by sewerage systems (Wastewater treatment plants connected with sewer systems)
2. Development of Safety City for Heavy Rain
Promotion of the comprehensive countermeasures for inundation in urban area by cooperative work with river section for flood control, aggressive installation of rainfall infiltration facilities, and preparing the hazard map indicating the area in danger of inundation
Ensuring the safety urgently in the area most likely suffered from severe inundation

Number of Flooded Houses Which Should be Eliminated Urgently
  about 90,000 households(2002) about 60,000 households(2007)
The number of houses which still have a high possibility of inundation among flooded houses in last 10 years

Accomplishment Rate of Countermeasures for Inundation by Sewer Systems     51%(2002) 54%(2007)
The ratio of area where stormwater drainage system are serviced to prevent inundation from rainfall that occurs with a probability of once every five years
to planning area to be provided with stormwater drainage system
3. Generation of Clean Water Environment
Promotion of the construction of advanced wastewater treatment facilities in addition to the promotion of conventional sewerage systems in the important area for water quality conservation
Urgent enforcement of Combined Sewer Overflow improvement to reduce the annual discharged pollutant loads from Combined Sewerage Systems as the same or less level of pollutant loads from Separate Sewer Systems, which is supposed as substitute of Combined Sewerage Systems

Percent of Population Served by Advanced Wastewater Treatment
                             11%(2002) 17%(2007)
Percent of population served by advanced wastewater treatment facilities which makes it possible to reduce the pollutant load of nitrogen, phosphorus, etc. as well as organic matter to the level regulated by Water Pollution Control Law and is closely connected with need for accomplishment of Environmental Water Quality Standards

Combined Sewer Overflow Improvement Rate    15%(2002) 40%(2007)
The ratio of area where the annual discharged pollutant loads from Combined Sewerage Systems is improved to the same or less level of pollutant loads from Separate Sewer Systems, which is supposed as substitute of Combined Sewerage Systems, to total area provided with Combined Sewerage Systems
4. Reduction of the Load to Environment Mainly Based on the
   Circulation
Promotion of effective use and reduction of the quantity of sewerage sludge
Promotion of the reduction of greenhouse effect gas such as dinitrogen monoxide, etc. contained in discharged gas from incinerator for sewerage sludge

Recycling Rate of Sewerage Sludge    60%(2002) 68%(2007)
Percent of sewerage sludge which is recycled to total generated sludge
(dry solid base)
5. Others: Thorough Utilization of Wastewater and Sewerage
   Fasilities
Generation of comfortable water environment by means of providing of highly treated water to amenity space, effective use of rainwater, tree planting on the roof of covered wastewater treatment plants, etc.
Highest utilization of wastewater and sewerage facilities by mitigation of urban heat island effect using spray of treated wastewater on the roads in urban area, installation of optical fiber as a means of communication and data transmission in the upper space in sewer pipes, effective use of heat and cool thermal energy which is contained in exhaust air or wastewater, etc.
Promotion of reconstruction or renovation of sewerage facilities according to the rational plan in order to maintain the function of facilities satisfactory.