While it's true that mature fescue can develop very deep roots in loose soil, watering that much, especially on new grass such as yours, is a waste of water and can lead to problems. This would be overkill even on mature, deep rooted fescue. A general rule is that grass needs one inch of water per week. This one inch should be applied in one or two deep waterings per week. This amount will be more in times of hot weather, and less in cooler weather. Fescue will tell you when it needs water as it's leaves will fold up and it will look thin and dark. New grass needs frequent watering due to it's shallow roots, but as it matures this frequent watering should be cut back.

Thank you so much for your response, with the hot summers we've had it becomes so frustrating trying to keep Fescue alive so this fall I seeded with 5 Star fescue in hopes it will do better.

If you live in Oklahoma, then it's going to be a struggle every summer. Tall fescue is a cool season grass, and while it does tolerate heat better than others like Kentucky bluegrass and perennial rye, it still prefers a more northern climate.

Again, thank you.