Drinking Water Management Act Article 14

Competent authorities at all levels shall select locations, conduct regular sampling and testing, compile and analyze data, and take appropriate measures based on the testing results. A competent authority shall officially announce promptly a prohibition on the consumption of drinking water for which it has been proven there is a concern about the endangerment of human health.Special municipality, county and city competent authorities shall report the sampling locations, testing results and adopted measures in the foregoing paragraph to the central competent authority.
中文原文 飲用水管理條例第14條
各級主管機關應選定地點,定期採樣檢驗,整理分析,並依據檢驗結果,採取適當措施。
經證明有危害人體健康之虞者,應即公告禁止飲用。
前項採樣地點、檢驗結果及採取之措施,直轄市、縣(市)主管機關應向中央主管機關報告。

English translation for reference only; the Chinese text prevails. Not legal advice.