水道水 (すいどうすい)tap-water

水道水, its kanji, and other words that share them.Open this graph

Kanji in 水道水

水みずwater (esp. cool, fresh water, e.g. drinking water)
水準すいじゅんlevel; standard
水道すいどうwater supply; water service
水面すいめんwater's surface
水俣病みなまたびょうMinamata disease
水泳すいえいswimming
水田すいでん(water-filled) paddy field
水産すいさんaquatic products; fisheries
北海道ほっかいどうHokkaido (island, prefectural-level administrative unit)
報道ほうどうreport (of news); reporting
道みちroad; path
道路どうろroad; highway
都道府県とどうふけんprefectures (of Japan); largest administrative divisions of Japan: Tokyo-to, Osaka-fu, Kyoto-fu, Hokkaido and the remaining prefectures
鉄道てつどうrailroad; railway
報道陣ほうどうじんpress corps
柔道じゅうどうjudo

See how 水道水 connects to the rest of Japanese.