In the Epic of Gilgamesh, Utnapishtim used bitumen to seal his flood vessel.
Utnapishtim is the flood survivor in the Babylonian epic, a figure whose story has important similarities to the Noah narrative. The god Ea warns him of a coming flood and tells him to build a large boat. In the account, bitumen is applied to make the vessel watertight, reflecting a practical building material used in ancient Mesopotamia.
Bitumen is a naturally occurring, viscous petroleum substance. Ancient Mesopotamian builders used it as waterproofing and adhesive, especially in a landscape where bitumen deposits were available. The material was therefore a realistic detail for a riverine or flood-vessel story.
The Epic of Gilgamesh is not the same text as Genesis, and Utnapishtim is not Noah’s name in the Babylonian tradition. Both narratives include a chosen survivor, a boat, animals, a devastating flood, and birds sent to test the waters, but their gods, characters, wording, and outcomes differ.