Which ancient Mesopotamian text tells of Atrahasis surviving a great flood in a boat?

The ancient Mesopotamian text about Atrahasis surviving a great flood in a boat is the Atrahasis Epic.

Written in Akkadian, the poem tells how the god Enki warns Atrahasis about a destructive flood. Atrahasis builds a vessel and preserves living creatures and people. The surviving tablets include a flood account with themes that also appear in the later Epic of Gilgamesh and in Genesis.

The text is important because it shows that flood-survivor traditions circulated in Mesopotamia in more than one literary form. Atrahasis is the hero’s name as well as the title commonly used for the work, and spellings vary, including Atra-Hasis and Atram-Hasis. It should not be confused with Enuma Elish, the Babylonian creation epic, or with the Code of Hammurabi, a law collection.