PFAS in tap water: Mie Prefecture

Levels by utility (PFOS + PFOA combined, ng/L)

These are the highest values in each fiscal year reported by each utility to the national government (MLIT and the Ministry of the Environment). A utility with several sources or treatment plants can have different levels in different parts of its area. Samples are taken at the tap in principle, but some utilities only measured raw water (water before treatment), and raw-water values are not covered by the tap-water standard. nd = below the detection or quantification limit; — = no value reported. *FY2025 covers results up to the end of August 2025. Utility names are left in Japanese as in the official table.

>50 a year above 50 ng/L (for utilities that also sampled raw water, the value may be from raw water)　raw above 50 ng/L, but measured in raw water only

Good to know

• In Kuwana, 290 ng/L was found at taps in the Tado-Oyama distribution area (多度小山配水区), supplied by the Tado-Chubu pumping station (多度中部送水場). In October 2022 the city shut down the Tado-Chubu station, switched to water from the Tado-Hokubu distribution station (多度北部配水場), and confirmed in later tests that levels were below the quantification limit (not detected) (MLIT case studies).
• Kuwana plans to build connecting pipes (pipes that link to another supply line) so that it can use a new water source it had been planning (a change in the intake point), and says it will test all taps and raw water once a year. It explained the situation to residents through the heads of the neighborhood associations and circulated notices (case studies, as of November 2024).
• The Yokkaichi City Water and Sewerage Bureau reported 11–25 ng/L (FY2020–FY2025), with testing points at the tap and the treatment plant outlet. Minamiise’s 16 (FY2024) is a “raw water only” value (raw water = water before treatment) in the table published in 2024.
• The Mie Prefectural Enterprise Agency’s bulk water supplies (Hokuchusei (北中勢) and Nansei-Shima (南勢志摩)) were nd in all six years. Among private water supplies (for a facility, such as company housing or hospitals), none of the 103 tested in the prefecture was found to exceed the provisional target value (through the end of August 2025).

Timeline

Put it in terms of your own intake

Related explainers

• What happened in areas where high PFAS values were found in tap water? A timeline of Kibichuo, Tama, Okinawa and more
• How do you check PFAS in your local tap water? Reading the national tables and working out “what percent of the TDI”
• Water filters and PFAS

Sources

• Ministry of the Environment and MLIT, “Survey on PFOS and PFOA in Water Supply,” follow-up survey: list of results (published December 25, 2025)
• Ministry of the Environment and MLIT, list of results (published November 29, 2024; testing point column)
• MLIT, “Cases of PFOS and PFOA responses by water suppliers to date” (November 29, 2024), Case 8: Kuwana City
• Same follow-up survey, attachment (status of private water supplies by prefecture)

Last checked 2026.10.04 (against the original government documents and papers, collected and cross-checked in Gemini Notebook). Utility values are as in the national table; Urayomi sorted and summarized them.

Other prefectures

• Shiga Prefecture
• Kyoto Prefecture
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• Wakayama Prefecture