Fontana Reservoir, located in the mountains of western North Carolina, covers 10,670 surface acres at full pool elevation of 1,710 feet. The reservoir is approximately 29 miles long, has 248 miles of shoreline, a maximum depth of 440 feet, and three influent rivers, the Nantahala, Little Tennessee, and Tuckaseigee. Temperature and chemical profiles were taken monthly from June 1964 through December 1965 at five permanent sampling stations. It was concluded from the study that: (1) During the summer, the Nantahala River water flows below the warmer Little Tennessee and Tuckaseigee River waters; (2) Two steep temperature gradients meeting the requirements of a thermocline definition were formed in Fontana Reservoir during each annual cycle; (3) No significant variations of alkalinity nor carbon dioxide concentrations were found in the reservoir; (4) Anaerobic decomposition of sludge deposits in the Tuckaseigee River arm resulted in the formation of a stratum of anoxic water in the main reservoir; (5) The anoxic water stratum was found to reach the penstocks in October at about the time of the fall overturn; and (6) At least five percent of the total reservoir capacity is removed from fish productivity by a complete absence of oxygen.
