Yes, the Bible does describe Jesus walking on water. This event is recorded in three of the four Gospels:
* Matthew 14:22-33: This passage describes Jesus sending his disciples ahead in a boat while he goes up on a mountainside to pray. Later, in the middle of the night, he walks on the lake toward them. The disciples are terrified, thinking he's a ghost, but Jesus tells them not to be afraid. Peter asks Jesus to call him out onto the water, and Peter briefly walks on the water towards Jesus before becoming afraid and starting to sink. Jesus rescues him.
* Mark 6:45-52: This account is similar to Matthew's, but shorter. It also mentions that the disciples were amazed, because they did not understand about the loaves (referring to the feeding of the 5000, an event that preceded the water-walking in both accounts).
* John 6:16-21: This version is even more concise. The disciples are crossing the lake in a boat, and Jesus comes to them, walking on the water. They are willing to take him into the boat, and immediately the boat reaches its destination.