Overview of water supply and sewerage systems in Japan

Transcription

1 Overview of water supply and sewerage systems in Japan Hiroaki FURUMAI Professor, Research Center for Water Environment Technology and Department of Urban Engineering Graduate School of Engineering, University of Tokyo Federation of Japan Water Industries Forum, Sep. 16,

2 World Ave. Japan Water resource and use in Japan 900mm/year 1700mm/year Evapotranspiration 230 Total Precipitation 640 Data from Water Resource in Japan (MLIT, 2016) Unit: Billions m 3 /year Reserved Water Resources 410 Surface water Base flow Flood flow Domestic use 15.1 Industrial use 11.1 Agricultural use 54.0 (3.1) (3.1) (2.9) Groundwater * Recycle ratio is about 80% in industrial sector. Federation of Japan Water Industries Forum, Sep. 16,

3 Significance of water supply and sewerage Water is a central element for drinking and for sanitation to sustain the health, livelihood, economy and the general living environment of city residents. As cities grow and their populations increase, water resource development is required and generated wastewater should be properly treated to conserve water environment. Sustainable and safe water supply and adequate wastewater treatment is one of city s key responsibilities. Federation of Japan Water Industries Forum, Sep. 16,

4 Hydrological circulation and urban water system Water flux by hydrological circulation Recovery of energy and water quality by solar energy Precipitation Dam Reservoir Gravitation energy consumption Water supply Water use WWTP DWTP Sewerage Water quality consumption Lake Evaporation Sea/Ocean Water catchment region Discharge/Reclamation region Reference: N. Tambo (1976) Journal JWWA Federation of Japan Water Industries Forum, Sep. 16,

5 Patient number and Population Coverage rate [%] Water supply and sewerage coverage in Japan Total Population [x 10 6 ] Patient number [x 10 3 ] 160 Water supply Coverage 80% Total Population 97.9% in 2016 Wastewater treatment coverage 100% 90.4% in % 78.3% in Patient number* Sewerage coverage 60% 40% 40 30% Rapid development 20% * Cholera, dysentery, typhoid, paratyphoid) Fiscal year 0% Federation of Japan Water Industries Forum, Sep. 16,

6 Annual fresh water volume by water treatment systems Total volume: Billion m 3 (FY 2014) Chlorination only Slow sand filtration Membrane filtration 17% 78% Rapid sand filtration Change from 1975 to 2014 Population => million Treated volume => Billion M 3 Water use volume 312 => 321 Liter/day/capita Advanced water treatment BM 3 in Federation of Japan Water Industries Forum, Sep. 16,

7 Effective water and accounted water ratio in 2014 <National average in 2014> Effective water ratio : 92.6 % => Leakage ratio: 7.4 % Accounted water ratio: 89.8 % Tokyo Berlin Los Angeles Moscow Madrid Sao Paulo Cairo Torino Istanbul Hong Kong London Bangkok Mexico City 3.6% Water leakage rate in major cities of the world 0% 5% 10% 15% 20% 25% 30% 35% 40% Federation of Japan Water Industries Forum, Sep. 16,

8 Domestic Wastewater Treatment Systems Sewerage system Sewage Treatment Plant Wastewater Treatment Rural sewerage system Sludge treatment On-site wastewater treatment tank (Johka-so) Sludge On-site night soil treatment tank Night soil storage tank Sludge Night soil Night soil treatment facility Federation of Japan Water Industries Forum, Sep. 16,

9 Annual Volume of Treated Wastewater Treated volume: Billion m 3 (FY 2012) 26.0% Advanced Primary 3.3% Only 1.45% Recycling rate Recycling/ reclamation volume: Million m 3 (FY 2012) Secondary 70.7% Federation of Japan Water Industries Forum, Sep. 16,

10 Wastewater Treatment Plants by Process [%] Others SBR Denitrification process AO Oxidation ditch A2O Conventional activated sludge process Design daily maximum dry weather flow [x10 3 m 3 /day] Federation of Japan Water Industries Forum, Sep. 16,

11 Generated Biosolids Volume and Its Recycle Green farm % Landfill Fuel Green farm % Landfill Fuel Green farm % Landfill Volume unit Million DS ton Ocean dumping Construction material (cement) Other without recyle Construction material (other than cement) Other effective utilization Federation of Japan Water Industries Forum, Sep. 16,

12 Changes of Urban and Rural Populations 100% Rapid development 30% of water supply 80% Japan Total population [Million] % 60% 40% 20% Rural 53% 72% Urban % Year 2018 Federation of Japan Water Industries Forum, Sep. 16,

13 Past and expected increase in urban population Japan China South-eastern Asia Federation of Japan Water Industries Forum, Sep. 16,

14 Population Growth and Mega Cities Globally, more people live in urban areas than in rural areas, with 54% of the world s population residing in urban areas in In 1950, 30% of the world s population was urban, and by 2050, 66% of the world s population is projected to be urban. As the world continues to urbanize, sustainable development challenges will be increasingly concentrated in cities with rapid development. Integrated management of urban water infrastructure to improve the lives of both urban and rural dwellers are needed. Federation of Japan Water Industries Forum, Sep. 16,

15 Concern about stable water supply and sewerage systems in growing cities Development of stable water supply and sewerage systems have become concerning in growing mega cities. Achievement of the sustainability is required ensuring a long-term water supply with adequate quality and minimizing adverse economic, social and ecological impacts. The history and experience of water supply and sewerage development in Japan may provide useful information to develop sustainable and safe urban water infrastructures and to find future possible tasks. It is meaningful to introduce our Japan struggling experiences of urban water infrastructure development. Federation of Japan Water Industries Forum, Sep. 16,

16 Thank you for your attention Overview of water supply and sewerage systems in Japan Hiroaki FURUMAI Professor, Research Center for Water Environment Technology and Department of Urban Engineering Graduate School of Engineering, University of Tokyo Federation of Japan Water Industries Forum, Sep. 16,