Otter Creek Reservoir is a high-elevation reservoir in southeastern Piute County, Utah, at about 6,372 feet above sea level near the southern end of Grass Valley. In a relatively remote part of the state, it is shown as a lake and is best known as a popular destination for rainbow trout fishing. The nearest town is Antimony, about 12 to 15 miles away, while Richfield is the larger city within roughly an hour’s drive. Today the reservoir serves both as a fishing destination and as an important mountain-valley water body in southern Utah.