Human waste (night soil) in cities was a valuable fertilizer 100 year ago Cities (towns) Human waste Agricultural products Farming villages in suburba

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1 IWA ASPIRE WS 4/Oct/2011 Tokyo International Forum Strategy for extending sanitation services by an integrated coverage with on-site and off-site systems in Japan Department of Urban Engineering, Graduate School of Engineering, University of Tokyo Dr Hiroyuki Katayama

Human waste (night soil) in cities was a

human waste in the City of Kyoto was 80,000 in

2 Human waste (night soil) in cities was a valuable fertilizer 100 year ago Cities (towns) Human waste Agricultural products Farming villages in suburban areas Sales amount of human waste in the City of Kyoto was 80,000 in 1909 (Equivalent to 80% of the city s tax revenues) ca

3 Public Health in 19th century Urbanization in European countries Movement of social issues and public health cause of disease Priority of civilization Supporter Miasma theory bad air Wastewater, Solid waste Poor law Edwin Chadwick, Max Josef von Pettenkofer Contagion theory Germ Drinking water John Snow Robert Koch 3

4 Impact of Cholera outbreaks First priority was set to prevent Cholera outbreak Water supply was focused since V. Cholera isolation by R. Koch (1884). Water supply was first proceeded also in Japan, followed by sewer system after World War II. 4

5 Spread of water supply and sewerage systems Spread of sewerage systems was 40 years behind water supply service 5

6 Development of chemical fertilizer (ammonium sulfate) consumption and changes of human waste disposal methods Start of the import of ammonium sulfate Start of domestic production of ammonium sulfate End of the purchases of human waste Establishment of human waste dumping sites at Sumida River Establishment of human waste disposal site in Ayase Ocean dumping by ironclad ship Railway transportation of human waste (million t) (Dictionary of Plant Nutrition and Soil Fertility: published by Yokendo, 1980) 6

Pollution and clean-up of Sumida River In Japan, legal and institutional improvement, in addition to technological development in the 1970s, has enabled the rapid increase of sewerage coverage,

Diffusion rate (%) 100 90 80 70 60 50 40 30 20 10 0 Diffusion of sewage systems and change in 下水道の普及と隅田川の水質の変化 water quality of Sumida River 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991

7 Pollution and clean-up of Sumida River In Japan, legal and institutional improvement, in addition to technological development in the 1970s, has enabled the rapid increase of sewerage coverage, leading to the improvement of river water quality and urban environments. Diffusion rate (%) Diffusion of sewage systems and change in 下水道の普及と隅田川の水質の変化 water quality of Sumida River Water 水質 (BOD)( quality (BOD) 隅田川 (Sumida ) River) 下水道処理人口普及率 (Diffusion rate of switch systems ( 全国 ) (Diffusion rate of switch systems against against population (nationwide) 下水道処理人口普及率 population (Sumida River) ( 隅田川 ) 水質 Water quality(ppm) ( p p m ) Polluted Sumida River in the 1970s Construction of sewage facilities Water quality improvement resulted in the restoration of a fireworks show on Sumida River 7

8 A Variety of Types of Sanitation Facilities in Japan Individual treatment <0.2% From open field dumping of human waste to domestic disposal Human Waste Vault toilet Banned in 2007 Ocean dumping Human waste (night soil) treatment facilities Flush toilet Banned in 2000 Tandoku-shori johkasou Gappei-shori johkasou Sludge Non-fecal wastewater Residence Wastewater treatment Untreated miscellaneous wastewater River and ocean etc. 8

9 History of Domestic Wastewater Management in Japan Population, million Individual management Dumping into the sea Night soil treatment plant Johkasou system 20 Public Sewerage system Year Development of domestic Wastewater management in Japan( ) 9

ago in major cities, as a countermeasure

prevention of spreading of epidemics through

10 Inception of sewerage in Japan Modern sewerage of Japan started about 130 years ago in major cities, as a countermeasure against flood by rainwater and for prevention of spreading of epidemics through sanitary wastewater. Mikawashima wastewater treatment plant, Tokyo (the first plant of this kind in Japan:1922) Brick-made sewer, Yokohama 10 City (1881)

11 Wastewater law Local government is primary responsible for public health and sound city environment as well as protection of public water body. To ensure the water quality, local governments plan, build and operate wastewater treatment systems. Rainwater management is also included. 11

12 コレラの流行浸水問題 Cholera epidemic, flooding Changing roles of sewerage systems Background 背景 Roles 下水道の役割 of sewerage systems 土地の清潔の保持 Maintaining the cleanliness of the area Sewerage laws 下水道法令明治 33 年 3 月 Mar.1900 Old 旧下水道法制定 version of Sewerage Law Enacted 土地の清潔の保持を目 aiming at maintaining the cleanliness of the area 的に規定 Applicable laws 関係法令 and regulations Heightened interest in 生活環境への関心の高まり living environments Deterioration of water 河川や海等の水質の悪化 quality of river and ocean Advent of of energy-saving/ 省エネリサイクル社会の到来 recycling-oriented society Heightened interest in 潤いのある空間への関心の高まり pleasant space 安全安心へのニーズの高まり Growing needs of safety and peace of mind Frequent floods in urban areas 都市型水害の頻発 Sluggish water quality improvement in closed 進まない閉鎖性水域の水質改善 water areas Response 地球温暖化への対応 to global warming Creation 循環型社会の構築 of a recycling society 都市の健全な発達公衆衛生の向上 Healthy development of urban areas Improvement of public health Water quality conservation in 公共用水域の水質保全 public water bodies Effective use of resources recovered 下水道資源等の有効利用 from sewage Creation 望ましい水循環水環境の of desirable water cycle and water environment 創出 Strengthening countermeasures 都市浸水対策の強化 against urban floods Regional 広域的な雨水排除 storm drainage 流域単位での高度処理の at river 推進 basin level Promotion of advanced treatment Change of the role of a sewerage system 健全な水循環資源循環を創 to a recycling system 出する循環のみち下水道への転換 that creates healthy water cycle and resources recycling 昭和 Dec 年 4 月 New Sewerage 新下水道法制定 Law Enacted aiming at improving urban environments 都市環境の改善公衆衛 and public health 生の向上を目的に規定昭和 Dec 年 12 月 Revised Sewerage Law 下水道改正 ( 公害国会 ) (Pollution session of the Diet) 公共用水域の水質保全 Enacted aiming at water quality conservation in public を目的に追加 water bodies 平成 Jun 年 6 月 Revised 下水道法改正 Sewerage Law *Obligation to make effort to 汚泥処理の努力義務付 treat sludge 光ファイバー *Optical fiber 平成 Jun 年 6 月 Act on Countermeasures against Flood 特定都市河川浸水被害対 Damage of Specified Rivers Running 策法制定 across Cities was enacted *Planning regional flood control measures 流域水害対策計画*Require drainage 排水設備の貯留浸透機 systems to be equipped with storage and infiltration capacities 能の義務付 Jun.2005 平成 17 年 6 月 Revised 下水道法改正 Sewerage Law *Regional rainwater sewer 雨水流域下水道 system *Promotion 高度処理の推進 of advanced 事故時の措置の義務付 wastewater treatment *Obligation to implement measures at the time of accidents Basic Act for Environmental 公害対策基本法 ( 昭和 Pollution 42 年 Control 8 月 ) Aug.1967 Water Quality Pollution Control 水質汚濁防止法 Act Dec.1970 ( 昭和 45 年 12 月 ) Environmental Basic Act 環境基本法 Nov.1993 ( 平成 5 年 11 月 ) 循環型社会形成推進基本法 Basic Act on Establishing a Sound Material-Cycle Society Jun.2000 ( 平成 12 年 6 月 ) 京都議定書発効 Enforcement of the Kyoto ( 平成 17 Protocol 年 2 月 Feb.2005 ) The Third Basic Environmental 第 3 次環境基本計画 Plan Apr.2006 ( 平成 18 年 4 月 ) 環境保全上健全な水循 Securing sound water cycle for environmental conservation 環の確保

13 Financial system supporting evolution of the sewerage service In view of personal benefits, such as flushing of toilets, and public policy objectives including water quality conservation of public water area and control of flood, the national government expenses, local expenditure, and charges have been properly combined to promote the sewerage service. 建設費の財源構成 Fund composition for construction costs 例 : 分流式下水道の管渠の場合 Example: Separate sewer system Subsidy Independent 補助単独 Fund composition for sewerage maintenance costs 下水道管理費の財源構成 Example: 例 : 処理区域内人口密度 Treatment area with 25~50 the internal 人 /hapopulation の地域 density of people/ha Stormwater 雨水 Wastewater 汚水 National government 国費 expense ( 国庫補助金 ) (Governmental subsidy) Sewage works construction bond 下水道事業債受益者負担金等 Users fee, etc. Sewage works construction 下水道事業債 bond Principal and interest redemption of bond 起債元利償還費 Maintenance 維持管理費 cost 10% 50% 40% Local grant tax inclusion ratio 交付税算入率 (60%*0.7 (60%*0.7=42%) = 42%) Stormwaterv 雨水 Stormwater 雨水 = public = 公費負担 expenditure Wastewater 汚水 Portion covered by public expenditure for 汚水のうち公費負担部分汚水のうち私費負担部分 Portion covered by the wastewater 分流式下水道等に要する経費 ( 使用料 private - Expenditure ) expenditure for 高資本費対策に要する経費 required for separate sewer wastewater (charge) system 等 - Expenditure to cope with high capital expenditure 13 13

14 Expanding coverage through well-planned investment in sewage works 14

On-site Sanitation Systems (Johkaso) and

and organic waste recycling center On-site

Treatment plant for rural areas(johkasou)

treatment (Tandoku-shori johkasou) Night

15 On-site Sanitation Systems (Johkaso) and night soil treatment Night soil treatment and organic waste recycling center On-site treatment plant (Johkasou) This type of Johkasou can be applied to organic pollutants removal as well as nitrogen and phosphorous removal On-site treatment plant for individual houses (Johkasou) Treatment plant for rural areas(johkasou) On-site treatment plant for black water treatment (Tandoku-shori johkasou) Night soil storage tank (Vault toilet) Biogas production Compost production 15

On-site treatment facilities (johkasou) in Japan Disinfection tank Inflow Discharge Settling tank Contact membrane Filter membrane Anaerobic filter tank (1 st chamber) Contact aeration tank

16 On-site treatment facilities (johkasou) in Japan Disinfection tank Inflow Discharge Settling tank Contact membrane Filter membrane Anaerobic filter tank (1 st chamber) Contact aeration tank Diffuser pipe Anaerobic filter tank (2 nd chamber) Treated water quality BOD <=20 mg/l Inflow Anaerobic filter tank Aeration tank Settling tank Disinfection tank Discharge Sludge Sludge 16 16

Advantages of On-site Sanitation Systems (Johkasou) Percentage, % Low initial investment cost, high treatment performance Little topographic limitation, short installation time and early

reuse Be flexible enough to respond to depopulation society Less vulnerable to earthquakes and other disasters 100 90 80 70 60 50 40 30 20 10 0 99.2 88.9 87.1 0.6 More than 1,000 6.2 7.2 82.

17 Advantages of On-site Sanitation Systems (Johkasou) Percentage, % Low initial investment cost, high treatment performance Little topographic limitation, short installation time and early realization of the effects Invaluable contribution to maintaining sufficient water in small rivers and aquatic environments near inhabited areas Johkasou-treated water and sludge are easy to reuse Be flexible enough to respond to depopulation society Less vulnerable to earthquakes and other disasters More than 1, (as of the end of FY 2007) 75.5 Sum of major domestic wastewater treatment systems Johkasou system 500-1, Less than 50 Size of municipalities, thousand 17

18 Johkasou Law and Service Population 1983: Johkasou Law, 1985 set into effect. Regulating manufacturing, installing, operating and sludge-disposal of johkasou. 1987: National subsidy program for individuals, 100 million yen. 1994: Subsidy to municipalities for promotion of gappei-johkasou 2000: Revision of Johkasou Law, banning tandoku-shori johkasou. 2004: National subsidy amounted 25.7 billion. 2008: Johkasou serves 11.3 million people, i.e. 8.9% of the total population. 18

19 Capita (Construction cost + maintenance cost) Sanitation systems based on careful study of population density and the cost Conceptual diagram of cost comparison 一人当たりのコスト ( 建設費 + 維持管理費 ) Balance point (Cost comparison must be made from a total view point covering the construction cost as well as the maintenance cost.) On-site treatment Off-site treatment Population density On-site treatment proves 区域は個別処理 economical for areas with thinly scattered population 人口が密集した区域 Off-site treatment proves は集合処理が経済的 economical for densely populated areas In comparing the cost per person between centralized treatment (sewerage systems, rural sewerage systems tec.) and individual treatment (gappei-shori johkasou), there is an equilibrium point, which is determined by the characteristics of the region. 19

Population density Choice of appropriate sanitation

density) and social overhead capital investment into

Night soil ) treatment Full-scale collective Sewerage

Combined household Wastewater treatment facility Degree of

20 Population density Choice of appropriate sanitation systems considering degree of urbanization (population density) and social overhead capital investment into account Human waste( Night soil ) treatment Human waste( Night soil ) treatment Full-scale collective Sewerage Ocean dumping Storage Pit Latrine Individual management Combined household Wastewater treatment facility Degree of progress of infrastructure improvements, including electricity and water supply 20

21 Conclusion History of sanitation in Japan: custom of storing Cause less environmental pollution From ocean dumping to night soil treatment Spread of flush toilets: further improvement of living environments Sewerage systems cover densely-populated areas and work as storm-water drainage facilities in urban areas (Tandoku-shori/gappei-shori) Johkasous cover thinlypopulated areas Japan s experience: key to the improvement of sanitation High coverage rate of Japan s sanitation services was realized by an ideal combination of on-site and off-site systems Financial support Regulations and standards / standardization Hygiene education 21

22 For more information about the presentation, please contact Secretariats of GCUS, JSWA staff, answer your inquiry on behalf of author after consultation with author. About GCUS, please access

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<95DB8C9288E397C389C88A E696E6462> 2011 Vol.60 No.2 p.138 147 Performance of the Japanese long-term care benefit: An International comparison based on OECD health data Mie MORIKAWA[1] Takako TSUTSUI[2] [1]National Institute of Public Health,