Introduction to High Quality Water Infrastructure in Japan

Dr. Satoshi Takizawa

Professor, Department of Urban Engineering, The University of Tokyo

644,723 km = 16 rounds of the earth

Total length of water supply pipes in Japan

Year2010 2011 2012

CategoryWater Supply 621,565 627,780 633,361

Raw Water Conveyance pipes 9,838 9,875 9,939

Water Transmission pipes 20,727 21,128 21,387

Water Distribution pipes 591,000 596,777 602,035

Bulk Water Supply 11,311 11,379 11,362

Raw Water Conveyance pipes 1,114 1,115 1,121

Water Transmission pipes 10,197 10,264 10,241

Total 632,876 639,159 644,7232

2010 2011 2015

Total Population 1,000 capita 128,000 127,713 127,440

Water Supply Population 1,000 capita 124,817 124,657 124,466

Coverage Ratio 97.5% 97.6% 97.8%

Daily Maximum Water Supply Volume 1,000 m3 48,149 47,240 46,383

Daily Average Water Supply Volume 1,000 m3 41,482 40,838 40,611

Waterworks in Japan

First Modern Waterworks: Yokohama in 1887Average Supply Volume: 326 LCD

3

Water Leakage: 7.2% (JPN Ave.)Tokyo Metro.: 2.0% (2012)

Reduction of Water Leakage

10.0%

9.8%9.7%

9.1%8.9%

8.7%8.6%

8.3%8.2%

7.9%

7.8%

7.6%

7.7%

7.5%7.3%

7.1%

7.2%

7.1%

7.6%

7.2%

5%

6%

7%

8%

9%

10%

11%

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011

2012

4Reduction of water loss

Energy recovery from sewage sludge

5

VVVF Inverter Pumps• Variable flow• Max. 50% energy saving

Small-scale hydro-power station

City-wide energy saving in Water Supply

6http://www.waterworks.metro.tokyo.jp/water/torikumi/kankyou/kankyokeikaku2013-2015pamphlet.pdf

Tokyo Waterworks: Environmental Plan 2013-2015

Direct Supply

Water Tanks

Water utility Water users

Energy consumption for water supply in Tokyo

Energy saving in 3 years:

Tokyo Olympic Game 2020

7

Water reclamation and reuse by advanced wastewater treatment

8

Ariake Water Reclamation Plant

Tokyo Big Sight

Toilet flushingTrain washing

Improvement of landscape water qualityODAIBA Seaside Park

Source: Bureau of Sewerage Works Bureau, http://www.gesui.metro.tokyo.jp/odekake/syorijyo/03_12.htm#shibaura_topMILT, http://www.mlit.go.jp/crd/city/sewerage/gyosei/shorisui.html

BOD < 1mg/LCOD 9mg/LT-N 11.5 mg/LT-P 0.3 mg/L

Annual use for environmental restoration

Energy recovery from sewage sludge

9

Egg-Shape Sludge Digester

Fuel Production from Sludge

10

Water shortage in Okinawa Island

Dams, National

Dams, prefectural

Dams, water utility

Middle Rivers

Northern Rivers

Western Rivers

WellsDesalination Plant

0 10km

Map of water resources in Okinawa(as of 2009)

New water resources

National Dams

Rubber Gate Dams

Traditional water sourceGroundwater

Okinawa Pref.Population: 1.3 millionTourist: 5 million/year

Desalination

11

0

50

100

150

200

250

300

0

500

1,000

1,500

2,000

2,500

3,000

3,500

1972 1977 1982 1987 1992 1997 2002 2007 Year

No-water days

PrecipitationPrec

ipita

tion

(mm

/yea

r)W

ater supply outage(days/year)

Water shortage in Okinawa Island

Supply outage

Desalination plant in full operation in 1997

Desalination capacity: 40,000 m3/dTotal supply volume in Okinawa: 420,000 m3/d

Western rivers(9 rivers)

+Northern river (2 rivers)

Fukuchi dam Kushi WTP

P

Nishihara WTP

P

P

Ishikawa WTP

Yamashiro dam

Kanna dam + Kin dam

Western rivers (3 rivers)

Hanechi dam

P

Chatan WTP

Kurashiki dam

Middle rivers

Wells

P

7,172

17,773

12,731

15,223

40,168

4,372

1,115

9,101

4,205

85,717

14,42414,133

Others 3,919

46,617

43,233

43,596

2,062

103,389

22,935

Nago WTP

7,608

59,349

10,2044,447

4,565

13,834

38,373

3,161

Industrial water

37.4

51.064.0

23.3

148.5

318.0

In:129.0, Out:124.0

In:33.0, Out:33.0

In:32.0, Out:32.0

In:55.0, Out:55.0

In:32.0, Out:32.0

Northern rivers (2 rivers)

6,038 92.045.2

166.9

51.0

34.0

28.0

221.0

92.0

P

WTP`

Pump

Raw water

Primary treaterd waterDistributed water

River

Well

Dam

FigHardness (mg/L)

Figure (10^3㎥/year)Water

Softening process

84.4

Figure (10^3㎥/year)

12

Water Systems in Okinawa Island: Multiple sources

Water Supply System in Japan

13

Integrated management of water systems

1. Increasing water use efficiency by water saving and demand reduction

2. Leakage control 3. Source water protection4. Advanced water treatment 5. Water quality management in pipes

and at points of use6. Anti-seismic structure and

countermeasures

Japanese water technologies supporting sustainable cities of the future

14

High efficiency pumps

System Integration Water reuse

NRW control

Advanced water treatment

Desalination

Hands-on training

Equipments

Sludge treatment and energy recovery

We welcome you to come and see the advanced water technologies in Japan.

Contact: Prof. Satoshi Takizawa, takizawa@env.t.u-tokyo.ac.jp