expression
like water; as if it were free; like it grows on trees
Used to describe spending money or using resources wastefully, as if they were as abundant and free as water. Often carries a negative or critical tone.
See also: 湯水
彼は湯水のようにお金を使う。
He spends money like water.
税金を湯水のように使うのは問題だ。
It's a problem to use tax money as if it were free.