Exodus 7:21

7:21 When the fish that were in the Nile died, the Nile began to stink, so that the Egyptians could not drink water from the Nile. There was blood everywhere in the land of Egypt!

Exodus 7:24

7:24 All the Egyptians dug around the Nile for water to drink, because they could not drink the water of the Nile.