The water of bilbao is commonly known to the champagne or Cava in the villa of Bilbao. The origin of this expression dates back to the beginning of the 20th century, when Bilbao flaunting its power were telling that in Bilbao he drank the champagne as if it were water, alluding to the economic power and the abundance of prosperous village. And that rigged today we have the expression water of Bilbao.
* Only one "like" per meaning and day, the more "likes" the meaning will appear higher in the list