You've probably seen signs like this that tell you that the shrubbery and the highway median and the local golf course is being watered with water that used to be in a sewage treatment plant.
你们也许都见过这样的牌子 上面写着灌木丛、高速公路隔离绿化带 本地高尔夫球场 的灌溉用水 都来自污水处理系统。