Watershed Management in Drinking Water for Emergency:
A Case of Lake Biwa - Yodo River System

Takashi SASAKI*1& Daiji NAGASHIO**Yodo River Water Quality Committee

1. Background
Lake Biwa - Yodo River water system is located in the middle west part of Japanand supports urban life and activities as one of the main water source for 14 million
consumers in the Kansai area (Fig. 1). The water system is characterized by urbanizationand developed industry in upstream area, at the same time, much use of domestic water indownstream area. This means the water is being reused so highly from upstream todownstream that there exist many kinds of risk factors to water safety.
Drinking water supply utilities taking water from the river organize “Yodo RiverWater Quality Committee” for integrated source water quality management to cope quickly
and systematically with source accidents. This paper describes outline of the Committee
and its source monitoring for emergency.
2. Outline of Yodo River Water Quality Committee
Fig. 2 shows yearly changes in raw water quality at Kunijima water treatment plant(WTP) of Osaka City, one of the largest utilities. Since the quality rapidly deteriorated due toincreased domestic and industrial wastewaters in 1960s, downstream utilities were forced
to take countermeasures for these problems. The utilities concluded that cooperative
approach for integrated source quality management was the best way and established
Yodo River Water Quality Committee in 1965, which is currently composed of ten utilities(Osaka Prefectural -, Osaka Municipal -, Moriguchi City -, Neyagawa City -, Hirakata City -,Suita City -, Amagasaki City -, Itami City -, Nishinomiya City - waterworks and Hanshin
Water Supply Authority) (Pic. 1). Since then, the Committee has engaged in various
activities for resource conservation including;* Technical administrator, Hanshin Water Supply Authority, 20-1 Nishi-okamoto 3-chome,Higashinada-ku, Kobe 658-0073, Japan (e-mail: sasaki-t@hansui.or.jp)** Director of water quality, Hanshin Water Supply Authority, 20-1 Nishi-okamoto 3-chome,Higashinada-ku, Kobe 658-0073, Japan (e-mail: nagashio-d@hansui.or.jp)- 117 -Kansai areaN030 km

Lake Biwa

Kyoto

Yodo RiverTokyoOsakaFig. 1 Outline of Lake Biwa - Yodo River water system

0.50KMnO
過ﾏﾝｶﾞﾝ酸ｶﾘｳﾑ消費量4 comsumption

ｱﾝﾓﾆｱ態窒素
Ammonia

150000BOD

10一般細菌Standard plate count

100000550000001897

1907

1917

1927

1937

1947

1957

19671977

1987

1997

FY

Fig. 2 Yearly changes in water quality of Yodo River

Pic. 1 Board Meeting of Yodo River Water Quality Committee- 118 -Standard Plate Count (CFU/mL)

1.0200000

15ＢＯＤ, KMnO 4 comsumption (mg/Ｌ)

Ammomia (mg/Ｌ)

1.5

･Regular monitoring of source quality･Research and investigation for source quality management･Advocating activities for pollution control･Awareness raising for resource conservation･Establishment of information networks for emergency control
3. Water Source Monitoring for Emergency(1) Information Networks for Emergency Control
In case of source accident, river administrator provides the Committee withinformation reported from the finder. Then the Committee informs all the members of theaccident according to emergency information networks rules (Fig. 3).
Fig. 4 shows changes in the number of source accidents. The number has been
increasing since 1990 after brief decline at around 1980. Severe accidents which directly
affect waterworks has been decreasing, on the other hand, the ratio of oil spill accidents
has been increasing in recent years. The Committee has periodically appealed toadministrative bodies to supervise the causative facilities, and achieved successful results.
An oil spill accident in October 2003 provides a good example. The accident
occurred at one of tributaries of Yodo River and affected downstream utilities. One of WTPs
was forced to stop water intake for four hours and six of WTPs had to reduce water intake,absorb oil, or use powdered activated carbon to cope with the spilled oil. Quick circulationof information followed by proper response to the accident prevented finished water frombeing contaminated. After that, four affected utilities claimed compensation from thecausative facility that the Committee identified.
(2) Organizing Watershed Data
Differences in the arrival time of contaminants from accident spot to intake points
are useful when accidents happen. The Committee developed “Arrival time display system
in Yodo River” based on observed time considering the effect of river shape and estuary
barrage. The Committee also created factories’ database in the basin named“Environmental map” (Fig. 5) containing their locations and harmful chemicals used toquickly respond to source accidents. The map can numerically display contamination riskby harmful chemicals in the whole area utilizing the stored data.

- 119 -Accident
FinderRiver Administrator

Neyagawa City
Waterworks

Osaka PrefecturalWaterworks

Hirakata City
Waterworks

Osaka Municipal
Waterworks

Accident
FinderHanshin Water
Supply Authority

Suita City
Waterworks

Moriguchi City
Waterworks

Itami City
Waterworks
Amagasaki CityWaterworks

Nishinomiya CityWaterworks

Fig. 3 Information networks for emergency control

The number of accidents

4035302520

the others
fish nosing or killcyanideunpleasant odor
coloroil1510501959 1963 1967 1971 1975 1979 1983 1987 1991 1995 1999 2003
FYFig. 4 The number of water source accidents in Lake Biwa – Yodo River water system- 120 -

Fig. 5 Part of environmental map in Yodo River basin
4. Summary
Delay in the response to accidents in the source may cause serious damages inthe social life, since the systems of waterworks being consisted of series of facilities fromsource to consumers’ tap and the systems are not free from vulnerability. In order to ensure
water safety, it is important to detect source accidents as quickly as possible and thenrespond to them properly. The Yodo River Water Quality Committee, a group ofdownstream water utilities of Yodo River being exposed to the high risk of accidents, jointly
monitors water source and engages in resource conservation activities. These efforts havebeen successfully assuring safety of drinking water so far.
There are other efforts in regard to watershed management. Review Panel on
Water Cycle Dysfunction Risk in Emergency, a panel established by government ministries,
is discussing cross-sectoral measures to avoid or reduce water quality risk in case ofearthquake, whose target area includes Yodo River basin. In addition, Kansai Waterworks
Association consisted of eight major utilities in the Kansai area has jointly been studying on“Kansai version of Water Safety Plan”. The developing process will include scientificevaluation on risk factors about their characteristics and risk levels. The goal is tocontribute to planning of source quality management and drinking water treatment.

- 121 -Lake Biwa – YodoRiver Water System

Lake Biwa

Watershed Management in
Drinking Water for Emergency:

Kyoto City

A Case of Lake Biwa - Yodo River System

Yodo RiverJapan
Yodo River Water Quality Committee

Osaka City

Takashi SASAKI, Daiji NAGASHIO
Osaka Bay

Okinawa

Changes in Raw Water Quality at
Kunijima WTP

Urbanization of Upstream

Establishment ofYodo River Water Quality Committee

Bacteria count (cfu/mL)

KMnO4 consumption (mg/L)
20

Musty Odor

KMnO4 consumption

15200000
150000Bacteria count10100000

5500000019001020

Establishment ofYodo River Water Quality Committee

30405060708090YearMembers• Why organized ?
– Urbanization and industrial development inupstream area
– Deterioration of water quality in Yodo River•
•••••
•
•••

• When established ?
– 1965• What purpose ?
– Cooperative approach for integrated source water
quality management

Osaka Prefectural Osaka Municipal Moriguchi City Neyagawa City Total Capacity (plan)
Hirakata City 7.2 million m3/d
Suita City Served population
Amagasaki City 11 million
Itami City Nishinomiya City Waterworks
Hanshin Water Supply Authority

Board Meeting

Activities

Regular monitoring

Research and investigationAwareness raising(Annual lecture meeting)

Advocating activities- 122 -Information networks
for emergency control

Research and Investigation

Regular Monitoring of Source Quality• Several working groups for special task
urgently needed• Monthly monitoring conductedwith cooperative system

Assignment• 20 Monitoring points¾Musty odor at Lake Biwa

• Over 160 of monitoring Items¾Precursors of trihalomethanes and agriculturalchemicals in the water source• Results summarized as
annual reports¾Development of useful tools for quick response
to water source accidents

Awareness Raising for
Water ResourceResource Conservation

Advocating Activities for Pollution Control
NationalNationalgovernment
government
RequestMinistry of• Posters andbrochures- Health, Labour and Welfare

Yodo
YodoRiverRiverWater
Water
Quality
QualityCommittee
Committee- Agriculture, Forestry and Fisheries- Economy, Trade and Industry- Land, Infrastructure and Transport- the Environment• Annual lecture
meeting

Request
Local
Localgovernment
government
Osaka prefecture
Kyoto prefecture and city
Other 6 administrative bodies

Information Networks for Emergency Control

Water Source Monitoring for Emergency

AccidentFinder• Information-sharing– Monitoring of source quality– Source accident– Research and investigation– Risk factors

RiverAdministrator• Control of pollutant source

Neyagawa
CityOsakaPref.

Hirakata
CityOsaka
CitySuitaCity– Advocating activities– Awareness raising

HanshinWaterMoriguchi
CityItami
CityAmagasaki
City

The Number of Water Source Accidents inLake Biwa -Yodo River Water System

The number of accidents

35302520

Nishinomiya
City

Case with Oil Spill Accident•

40

Accident
Finderthe others
fish nosing or killcyanideunpleasant odorcoloroil•

Diesel oil spill from a gas station to atributary stream
6 WTPs suffered damage– Oil removal, PAC, increase of ozone dose,reduction of water intake– One WTP stopped taking water for 4 hours.

15

•••

10501959 1963 1967 1971 1975 1979 1983 1987 1991 1995 1999 2003
FY

- 123 -

No contamination of finished water
Identification of causative facility
Claim for compensation

“Arrival Time Display System”
System”
and“Environmental Map”
Map” in Yodo River“Arrival Time Display System”
System”• To respond to source accidents
quickly and properly

Select certain two points“Arrival Time Display System”
System”“Environmental Map”
Map”
Information system combining factory database and GIS

The least time required between thepoints and average flow rate is displayed.

Number of factory data

6,500

Area on the system

25 cities, wards and counties in theYodo River water system

Type of industry

31 types

Data item

15 items (address, chemicals used,volume of discharge etc.)

SoftwareExclusive Mapping Soft (ProAtlas)

Additional function

Reference to the factories’
information, output of the file

Search function

Address, chemicals used and pointof discharge“Environmental Map”
Map”
Effects of Cooperative Activities• Reduction in cost concerning waterconservation• Prompt countermeasure for unexpected
pollution• Powerful advocating activities to national
and local government

ClickDisplay
Factory data
Used chemicals

Other Efforts of Watershed
Management in Drinking Water

Summary• Review Panel on Water Cycle Dysfunction Risk
in Emergency• It is important to detect resource accidents
as quickly as possible and respond tothem properly.
• Yodo River Water Quality Committee
jointly monitors water source and engages
in resource conservation activities.

– Established by government ministries– To avoid or reduce water quality risk in case ofearthquake• Kansai version of Water Safety Plan
– Kansai Waterworks Association (8 major utilities)– To contribute to planning of source quality
management and drinking water treatment• To assure safety of drinking water- 124 -