1 Specific Fic: Enki + Enlil meet Castiel

[ammykoss.livejournal.com]

Hello! I'm looking for a fic I don't remember the name of. Sam and Dean go to one of the Great Lakes, I believe, and find that all the fish in it has died and everything stinks. And there's a horrible heatwave. Castiel then appears, seems confused, and they go into caves to find the culprit.

Dean and Sam are reincarnations (maybe) of Enki and Enlil, two human hunters who existed in the times of Gilgamesh (I think). There's non-stop rain and so the harvest is ruined. Priests ask these brothers to do something, so they summon the one responsible for the rain. Castiel shows up. He says he was instructed to cause a Flood.