Measurement results of radioactive materials in tap water and raw tap water

In Yokohama City, the Ministry of Health, Labour and Welfare's notice “Settings of Management Target Values for Radioactive Materials in Tap Water” (No. 0305 No. 2 from Kensui on March 5, 2012 (PDF: 393KB)) measures radioactive materials in tap water and tap water (water before water purification treatment) at three water purification plants in the city. Tap water is collected at the outlet of the reservoir at each water purification plant, and tap water is collected at the entrance of each water purification plant.
Please refer to the water quality inspection point for the water distribution area of the water purification plant.
Results for this fiscal year and the past five years are posted.
※As for the measurement result of radioactive material in water purification plant of Kanagawa wide area water supply corporation which supplies tap water to Yokohama-shi, please see homepage of Kanagawa wide area water supply corporation from the following related link.

All measurement results of water treatment plants have not been detected so far.

Because all measurement results of city hydrant were not detected so far, we finish measurement at the end of 2020.
Please refer to the water quality inspection point for the water sampling point of the nearby hydrant.

In Yokohama city, water is supplied from the following water purification plants.

• City of Yokohama, Water Works Bureau water purification plant: Kosuzume Purifiction Plant, Nishiya water purification plant, Kawai Purification Plant
• Water purification plant of Kanagawa Prefectural Wide Area Water Supply Corporation: Ayase Water Purification Plant, Sagamihara Water Purification Plant, Nishi-Nagasawa Water Purification Plant

• Inspection of radioactive materials in tap water (City of Yokohama, Water Works Bureau)
• Measurement results of Kanagawa Prefectural Wide Area Water Supply Corporation (Kanagawa Prefectural Wide Area Water Supply Corporation) (outside site)
• Q&A of radioactive materials contained in tap water (City of Yokohama, Water Works Bureau)
• Radiation Q&A (National Research and Development Agency Institute of Quantum Science and Technology) (external site)