1. Why sewage works is essential to cities?
		When we develop cities, the cities have sanitation problems.
		To solve the problems sewage facility is the effective answer.
		Japan has made a great effort for installing the sewer system.
		In 1901 the Sewerage Law was enacted and in 1970 it was revised,
		as it was recognized that sewers were indispensable in maintaining
		water quality of public water bodies clean.
	2. Percentage of sewered population
		The percentage of sewered population is shown in (Figure-1).
	3. Treatment plants
		The types of processes used at sewage treatment plants in Japan
		are shown in the (Table-3).
		Of the 1622 treatment plants, 693 sites adopt conventional activated
		sludge process.
	4. Bodies to implement sewage works
		The sewage works in Japan are implemented mainly by Ministry of
		Land. Infrastracture and Transport (MLIT), Prefectures and
		Municipalities, and Japan Sewage Works Agency (JS).
		Regording the main roles and activity of these organization, please
		refer to following page.
	5. Infrastructure Intensive Development Plan
		Infrastructure Intensive Development Plan including sewerage
		facilities was decided by cabinet on Oct. 10, 2003. In this plan,
		principal objects and target outcome in 2007 for each facilities like
		roads, airports, rivers, etc., as well as sewerage facilities, were set
		up to promote the project intensively and effectively. In the field of
		sewage works, five principal objects and relating targer outcome were
		decided. In detail of this plan, please refer to following page and
		SBMC Newsletter Vol.1 No.4.