The Social Experiment for the
Horikawa River Clarification• Achievement of the Raw Water Transmission• Survey results by Nagoya city

Horikawa River General Development Office1

Results of the Raw Water Transmission from the Kiso
River from Apr. 22nd 2007 to Mar. 22nd 2010
Transmission Volume

Total: 21,810,000m3

2007

6,670,000m3

2008

7,140,000m3

2009

8,000,000m3

Running Hours
Down Hours

17,774.9 hr
7,797.2 hr

741 days
325 days

Drought

2,700.3 hr

113 days

Heavy Rain

2,581.6 hr

108 days

Others2,515.3 hr

105 days

Running Rate

69.5%2

Results of the Raw Water Transmission from the Kiso
River from 22nd. Apr. 2007 to 22nd. Mar. 2010
Million m3
Monthly Volume (Left Axis)

Sum Total (Right Axis)
25

1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0

Total: 21,810,000m3 →20
15105Feb. 2010

Dec. 2009

Oct. 2009

Aug. 2009

Jun. 2009

Apr. 2009

Feb. 2009

Dec. 2008

Oct. 2008

Aug. 2008

Jun. 2008

Apr. 2008

Feb. 2008

Dec. 2007

Oct. 2007

Aug. 2007

Jun. 2007

Apr. 2007

03

The Shonai River

ThSanage Bridge ●eYadaKitashimizu Bridge ●Injection Point of TRWKR
19Nagoya CastleJRChuo● Koshio Bridge

Nagoya StationRiver

Line22

TheHorikawa River

The Key
Investigation Spotsof AdministrationSurvey● Motoiri Sliceway

41● Nayabashi Bridge
Matsushige Gate
TheLineShiratori Bridge

247

１oyaNagtsu

Kizaemon Bridge ●23te
M ei
Line

idooka
JR Tn
JR
anse
ShinkLine

Nakagawa
Canal

１er
Rivawaorikn-H
Shi

Otobashi Bridge ●● Minatoshinbashi Bridge

Horikawaguchi Gate
Nagoya Port4

Administration Survey※ Data of TRWKR test period from 2007 to 2010
mg/L

BOD (Average from Apr. to Jun.)10.1

108Sanage Bridge

MotoiriSliceway0

1.8 2.5

3.5
2.7

OtobashiBridge2.0

Kitashimizu
Bridge22.6

2.9 2.5

Injection Point of TRWKR

2.4

2.8

3.8
3.3

Nayabashi
Bridge4.5

45.15.05.4

5.4

Koshio Bridge

66.5

6.6

6.1

5.5

5.2

4.5

Minatoshinbashi
BridgeBefore TRWKR
During TRWKR
After TRWKR

Kizaemon
Bridge12※ The water quality survey was carried out
at falling tide during neap tide period.

5Administration Survey※ Data of TRWKR test period from 2007 to 2010
mg/L

DO (Average from Apr. to Jun.)

12108

7.7 7.6 7.7
7.2

8.4 8.6
6.4

Before TRWKR
During TRWKR
After TRWKR

7.2 7.3

6

8.2
6.4

6.6
5.2
4.1 3.94

9.7

4.54.5
4.0

4.9
4.2

6.1
4.6

3.6

Minatoshinbashi
BridgeKizaemon
BridgeOtobashiBridgeNayabashi
BridgeKoshio Bridge

Kitashimizu
BridgeSanage Bridge

MotoiriSliceway

0Injection Point of TRWKR

2※ The water quality survey was carried out
at falling tide during neap tide period.

6

Glossary
BOD （Biochemical Oxygen Demand）
BOD describes the amount of oxygen consumed when microbes
degrade organic compounds in water. It is determined by theamount of organic compounds in drainage water flowing in theriver measured by activity of microbes. It is commonly used toshow the level of organic pollution in the river.

DO （Dissolved Oxygen）
DO means dissolved oxygen in water. It is necessary for water
creatures to live and is also necessary for self-purification of theriver and lakes. When drainage water flow in and pollute the water,
DO is consumed to degrade organic compounds and is decreased.
On the other hand, photosynthesis by algae increases DO. If it shows
less than 3mg/L, fishes hardly survive.
7