flat water meaning in English

平川之水
平静的水面

Expected swim conditions : warm , flat water . while the swim course is in the open south china sea , any significant swell , surf or chop is unlikely
理想的游泳环境：温暖的海水，风平浪静的海面，当在这中国南部的公开海域游泳的环节，不希望有任何的风浪或海潮发生。
Lay - flat water discharge hose is light in weight , and flexible with good cold and hot resistance , high working pressure , it is ideal tool for pump , water discharge in agriculture and building
质轻,柔软,存放占用用空间小,耐候性好,使用压力高,是水泵的配套用管,农业灌溉,建筑工程排水的理想管材