Did an eruption of water ocurred in the past?

Time ago I used to read the bible. In the passage of the flood in genesis, When I read that the fountains of the great deep burst forth, it didn't make sense, I even considered an addenda or an error of a copyist. Then I was watching one of the programs of the geology of the Sahara, when I watched that a huge lake was found beneath the surface of the dessert, it didn't make sense either. Then I remembered the passage of the bible and both had sense. I thought that it could have been huge lakes under the earth in the past when more dried land was exposed, then somehow, these lakes burst, tsunamiing the earth, flooding it, causing great damage. What are the chances that huge quantities of waters are contained very deep?