The emergency response headquarters of Fukushima Prefecture announced, on 16 March 2011, that abnormal radioactive elements have been found in Fukushima City tap water: radioactive iodide, at the level of 177 becquerel per kilogram; cesium, 58 becquerel per kilogram. They are still below the national safety standards for food and water intakes during a nuclear emergency (300 becquerel for radioactive iodide, 200 becquerel for cesium). However, the Fukushima Prefecture government says it will test samples from all the water sources in the prefecture, more closely monitor them, and make the data collected available to the public to allay their concerns.
The text above combines and translates information from an article published by Asahi Shimbun (16 March 2011, 22:01) and the Asahi TV video above (released on 16 March 2011). Translation by Yoshie Furuhashi (@yoshiefuruhashi | yoshie.furuhashi [at] gmail.com).