悪水[akusui] undrinkable water
井戸水[idomizu] well water
一衣帯水[ichiitaisui] (being separated only by a) narrow strip of water
一水[issui] current (of water)
溢水[issui] inundation

飲水量[insuiryou] amount of drinking
飲料水[inryousui] drinking water
烏の行水[karasunogyouzui] quick bath
雲水[unsui] itinerant priest
塩化水素[enkasuiso] hydrogen chloride

汚染源[osengen] source of pollution
音源[ongen] sound source
禍源[kagen] source of misfortune
供給源[kyoukyuugen] source of supply
経営資源[keieishigen] management resource

源氏物語[genjimonogatari] the Tale of the Genji
源泉[gensen] source
源流[genryuu] current-limiting
語源[gogen] word root