For inquiries regarding water supply, please contact the Water Works Bureau Customer Service Center.
Water Works Bureau Customer Service Center
Telephone: 045-847-6262 Fax: 045-848-4281
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- Results of water quality inspection
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Results of water quality inspection
Last Updated February 10, 2025
Results of water quality inspection
We confirm the safety of tap water quality by conducting water quality tests at inspection points established by Yokohama City.
The hydrant (faucet) publishes the results of water tests conducted every month, and the water purification plant publishes the results of water tests conducted in May, August, November and February.
For the measurement results of organic fluorine compounds, see the page on test results of organic fluorine compounds (PFAS) in tap water.
Water quality inspection points
Water tap (faucet)
2024 water examination result (water tap) (Excel: 742KB)
2023 water examination result (water tap) (Excel: 905KB)
Water purification plant
2024 water examination result (water purification plant) (Excel: 615KB)
2023 water examination result (water purification plant) (Excel: 777KB)
Related link
Water quality inspection items
Annual water quality test report
Measurement results of radioactive materials in tap water and raw tap water
About test result of organic fluorine compound (PFAS) in tap water
Inquiries to this page
Water Quality Division, Water Works Bureau Water Purification Department
Telephone: 045-371-5656
Telephone: 045-371-5656
Fax: 045-371-6942
Email address: su-suishitsu@city.yokohama.lg.jp
Page ID: 833-439-187
