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- Preliminary figures of river water quality measurement results (FY2022)
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Preliminary figures of river water quality measurement results (FY2022)
On this page, based on the public water quality measurement plan formulated by Kanagawa Prefecture, hydrogen ion concentration (pH), biochemical oxygen demand (BOD), suspended solids (SS) and dissolved oxygen (DO) are measured at 11 locations in rivers. Shows the changes in the monthly average of dissolved oxygen (DO) in the 2022 survey. Note that the measured values are preliminary figures and may be revised at a later date during the data determination process.
Last update date April 1, 2024
Click here for the layout of the measurement point.
Monthly average trends in rivers
Hydrogen ion concentration
| Water area name | River Name | Name of measurement point | Environment Criteria Type |
4 MON 13 SUN |
5 MON 11 SUN |
6 MON 1 SUN |
7 MON 14 SUN |
8 MON 3 SUN |
9 MON 7 SUN |
10 MON 6 SUN |
11 MON 9 SUN |
12 MON 7 SUN |
1 MON 11 SUN |
2 MON 1 SUN |
3 MON 1 SUN |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Tsurumi River | Tsurumi River | Sendai Bridge | Ｄ | 7.9 | 7.5 | 7.5 | 7.4 | 7.7 | 7.3 | 7.3 | 7.5 | 7.6 | 7.5 | 7.4 | 7.6 |
| Onda River | Miyakobashi Bridge | Ｄ | 7.9 | 7.5 | 7.7 |
7.6 | 7.8 | 7.4 | 7.4 | 7.6 | 7.6 | 7.5 | 7.3 | 7.5 | |
| Irie River | Irie River | Irie Bridge | Ｂ | 8.0 | 7.9 | 7.7 | 7.6 | 8.1 | 7.4 | 7.8 | 7.8 | 7.6 | 7.6 | 7.9 | 7.9 |
| Katabira River | Katabira River | Suidobashi | Ｂ | 8.4 | 8.2 | 8.2 | 8.1 | 8.2 | 8.0 | 7.9 | 7.9 | 8.0 | 8.0 | 8.0 | 8.1 |
| Ookagawa | Ookagawa | Shimizu Bridge | Ｂ | 8.2 | 8.3 | 8.2 | 7.9 | 8.2 | 7.9 | 7.8 | 8.0 | 7.9 | 8.1 | 8.1 | 8.3 |
| Miyakawa | Miyakawa | Seto Bridge | Ｂ | 8.3 | 8.2 | 8.2 | 8.2 | 8.1 | 8.1 | 7.9 | 8.0 | 8.0 | 8.1 | 8.1 | 8.1 |
| Samurai River | Samurai River | Hiragata Bridge | Ｂ | 8.3 | 8.2 | 8.2 | 8.2 | 8.3 | 8.2 | 8.0 | 8.0 | 7.9 | 8.2 | 8.2 | 8.2 |
| Sakaigawa | Sakaigawa | Takakamabashi | Ｄ | 8.0 | 8.0 | 7.7 | 7.6 | 7.8 | 7.7 | 7.7 | 7.8 | 7.8 | 7.8 | 7.7 | 7.9 |
| Kashio River | Yoshikura Bridge | Ｃ | 8.2 | 8.2 | 8.2 | 8.1 | 8.2 | 8.1 | 7.8 | 8.2 | 8.1 | 8.2 | 8.2 | 8.3 | |
| Kashio River | Takasho Bridge | Ｃ | 8.0 | 7.9 | 7.8 | 7.7 | 7.8 | 7.8 | 7.4 | 7.7 | 7.7 | 7.8 | 7.4 | 7.7 | |
| Itachi River | Itachikawa Bridge | Ｃ | 8.0 | 7.9 | 8.0 | 7.8 | 8.0 | 7.8 | 7.6 | 7.7 | 7.8 | 7.7 | 7.5 | 7.7 |
Biomass Oxygen Consumption (BOD)
| Water area name | River Name | Name of measurement point | Environment Criteria Type |
4 MON 13 SUN |
5 MON 11 SUN |
6 MON 1 SUN |
7 MON 14 SUN |
8 MON ３ SUN |
9 MON 7 SUN |
10 MON 6 SUN |
11 MON 9 SUN |
12 MON 7 SUN |
1 MON 11 SUN |
2 MON 1 SUN |
3 MON 1 SUN |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Tsurumi River | Tsurumi River | Sendai Bridge | Ｄ | 9.3 | 3.9 | 4.6 | 4.6 | 2.4 | 2.6 | 3.3 | 2.6 | 3.3 | 11 | 16 | 13 |
| Onda River | Miyakobashi Bridge | Ｄ | 11 | 7.9 | 6.7 | 8.2 | 9.0 | 7.8 | 2.8 | 9.1 | 1.8 | 13 | 14 | 13 | |
| Irie River | Irie River | Irie Bridge | Ｂ | 1.1 | 1.2 | 2.3 | 3.4 | 2.6 | 1.4 | 1.3 | 1.0 | 1.4 | 0.8 | 0.9 | 1.1 |
| Katabira River | Katabira River | Suidobashi | Ｂ | 0.7 | 0.7 | 1.0 | 2.6 | 1.2 | 1.3 | 1.1 | 1.0 | 0.8 | 1.1 | 1.1 | 1.2 |
| Ookagawa | Ookagawa | Shimizu Bridge | Ｂ | 1.1 | 0.7 | 1.3 | 1.4 | 1.8 | 2.0 | 1.4 | 1.0 | 0.6 | 1.0 | 0.8 | 1.0 |
| Miyakawa | Miyakawa | Seto Bridge | Ｂ | 1.1 | 1.3 | 1.2 | 2.2 | 0.9 | 1.7 | 0.9 | 0.8 | 0.5 | 0.8 | 0.8 | 1.0 |
| Samurai River | Samurai River | Hiragata Bridge | Ｂ | 0.9 | 1.3 | 1.0 | 2.4 | 2.3 | 2.0 | 1.1 | 1.1 | 0.6 | 1.2 | 1.0 | 1.4 |
| Sakaigawa | Sakaigawa | Takakamabashi | Ｄ | 1.1 | 2.3 | 1.0 | 1.4 | 0.7 | 1.0 | 1.3 | 0.7 | 1.0 | 2.2 | 4.0 | 1.5 |
| Kashio River | Yoshikura Bridge | Ｃ | 0.6 | 0.7 | 0.7 | 1.1 | 1.0 | 0.6 | 1.2 | 0.9 | 0.6 | 1.2 | 0.6 | 1.1 | |
| Kashio River | Takasho Bridge | Ｃ | 1.6 | 1.5 | 1.7 | 1.6 | 1.9 | 1.3 | 2.0 | 3.1 | 1.3 | 3.5 | 8.0 | 2.0 | |
| Itachi River | Itachikawa Bridge | Ｃ | 1.0 | 1.0 | 0.9 | 0.9 | 0.9 | 1.0 | 1.2 | 1.1 | 0.8 | 3.0 | 2.1 | 2.3 |
Suspended Substances (SS) ： (mg/l)
| Water area name | River Name | Name of measurement point | Environment Criteria Type |
4 MON 13 SUN |
5 MON 11 SUN |
6 MON 1 SUN |
7 MON 14 SUN |
8 MON ３ SUN |
9 MON 7 SUN |
10 MON 6 SUN |
11 MON 9 SUN |
12 MON 7 SUN |
1 MON 11 SUN |
2 MON 1 SUN |
3 MON 1 SUN |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Tsurumi River | Tsurumi River | Sendai Bridge | Ｄ | 4 | 3 | 3 | 8 | 4 | 3 | 3 | 3 | 3 | 4 | 7 | 7 |
| Onda River | Miyakobashi Bridge | Ｄ | 5 | 2 | 3 | 9 | 3 | 3 | 2 | 3 | 1 | 3 | 4 | 5 | |
| Irie River | Irie River | Irie Bridge | Ｂ | 2 | 2 | 3 | 6 | 4 | 2 | 2 | 2 | 2 | 1 | 3 | 2 |
| Katabira River | Katabira River | Suidobashi | Ｂ | 2 | 3 | 3 | 5 | 3 | 3 | 4 | 3 | 2 | 2 | 3 | 8 |
| Ookagawa | Ookagawa | Shimizu Bridge | Ｂ | 2 | 4 | 8 | 6 | 4 | 4 | 4 | 2 | 2 | 1 | 2 | 2 |
| Miyakawa | Miyakawa | Seto Bridge | Ｂ | 3 | 5 | 4 | 5 | 2 | 3 | 2 | <1 | 2 | 1 | 2 | 1 |
| Samurai River | Samurai River | Hiragata Bridge | Ｂ | 2 | 3 | 2 | 4 | 4 | 2 | 3 | 2 | 1 | 2 | 3 | 2 |
| Sakaigawa | Sakaigawa | Takakamabashi | Ｄ | 4 | 5 | 2 | 2 | 1 | 1 | 2 | 2 | 2 | 2 | 2 | 5 |
| Kashio River | Yoshikura Bridge | Ｃ | 2 | 3 | 4 | 3 | 4 | 5 | 3 | 1 | 2 | 1 | 1 | 6 | |
| Kashio River | Takasho Bridge | Ｃ | 4 | 2 | 3 | 4 | 3 | 4 | 4 | 3 | 2 | 2 | 3 | 3 | |
| Itachi River | Itachikawa Bridge | Ｃ | 3 | 2 | 2 |
3 | 3 | 5 | 3 | 3 | 1 | 2 | 3 | 4 |
Dissolved Oxygen (DO)
| Water area name | River Name | Name of measurement point | Environment Criteria Type |
4 MON 13 SUN |
5 MON 11 SUN |
6 MON 1 SUN |
7 MON 14 SUN |
8 MON ３ SUN |
９ MON 7 SUN |
10 MON 6 SUN |
11 MON 9 SUN |
12 MON 7 SUN |
1 MON 11 SUN |
2 MON 1 SUN |
3 MON 1 SUN |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Tsurumi River | Tsurumi River | Sendai Bridge | Ｄ | 7.4 | 7.1 | 6.6 | 5.9 | 5.9 | 5.5 | 7.2 | 6.8 | 8.6 | 7.1 | 6.9 | 6.5 |
| Onda River | Miyakobashi Bridge | Ｄ | 6.8 | 6.8 | 6.1 | 6.6 | 5.4 | 5.8 | 7.3 | 5.7 | 7.9 | 6.4 | 6.9 | 6.0 | |
| Irie River | Irie River | Irie Bridge | Ｂ | 8.6 | 7.5 | 5.3 | 5.3 | 8.1 | 4.2 | 6.0 | 6.9 | 6.1 | 7.7 | 9.0 | 9.2 |
| Katabira River | Katabira River | Suidobashi | Ｂ | 9.5 | 9.1 | 8.6 | 8.0 | 7.6 | 7.7 | 9.0 | 9.4 | 10.1 | 12.1 | 11.3 | 10.6 |
| Ookagawa | Ookagawa | Shimizu Bridge | Ｂ | 8.0 | 8.0 | 7.4 | 5.7 | 6.4 | 5.9 | 7.8 | 9.0 | 8.9 | 10.1 | 9.8 | 11.5 |
| Miyakawa | Miyakawa | Seto Bridge | Ｂ | 9.8 | 9.0 | 7.6 | 7.2 | 6.6 | 6.9 | 6.7 | 7.3 | 8.6 | 10.0 | 10.3 | 9.9 |
| Samurai River | Samurai River | Hiragata Bridge | Ｂ | 11.2 | 8.4 | 8.0 | 8.2 | 8.2 | 7.6 | 7.2 | 7.9 | 9.0 | 11.5 | 11.1 | 10.1 |
| Sakaigawa | Sakaigawa | Takakamabashi | Ｄ | 9.6 | 10.1 | 8.3 | 7.3 | 7.0 | 7.5 | 9.1 | 9.3 | 10.0 | 9.7 | 9.5 | 9.7 |
| Kashio River | Yoshikura Bridge | Ｃ | 10.0 | 10.3 | 9.5 | 8.0 | 7.9 | 8.2 | 8.7 | 10.0 | 10.6 | 11.5 | 11.7 | 10.3 | |
| Kashio River | Takasho Bridge | Ｃ | 10.2 | 9.8 | 8.9 | 7.7 | 7.1 | 8.1 | 8.0 | 8.2 | 9.5 | 9.3 | 9.5 | 9.4 | |
| Itachi River | Itachikawa Bridge | Ｃ | 9.7 | 9.6 | 9.0 | 7.7 | 7.9 | 8.0 | 8.2 | 8.4 | 9.4 | 8.9 | 8.8 | 8.8 |
For inquiries to this page
Environmental Pollution Monitoring Center Environmental Management Division, Environmental Conservation Department, Green Environment Bureau
Phone: 045-671-3507
Phone: 045-671-3507
Fax: 045-681-2790
Email address: mk-kankyokanri@city.yokohama.lg.jp
Page ID: 633-577-537
