Between December 2017 and July 2019 water column processes, manganese and nutrients were studied in Kelly’s Off Stream Storage, Byfield, Central Queensland, Australia. This off stream storage is a man-made dam that pumps water from Water Park Creek in the Byfield National Park. The source of the water is in the sand dunes of the Dismal Swamp. The catchment of the storage has controlled access, is well vegetated and not developed.
There is no flow other than the pipe which pumps from Water Park Creek. The storage stratifies in the summer with an anoxic hypolimnion and mixes in the cooler months. Mixing does not occur rapidly but over a period of months. This creates a well oxygenated surface layer throughout the year. The advantage of this is continual oxidation of dissolved manganese released from the anoxic hypolimnion. This reduces the concentration of manganese found in the surface layer and reduces impacts for the nearby Woodbury Water Treatment Plant and Yeppoon and Capricorn Coast potable water supply.
Cyanobacteria were not detected during this study even though this is a stratified water body that experiences high temperatures in summer. Key to the quality of this water is the sand filtration in the dunes upstream from Waterpark Creek, quality of the catchment, riparian vegetation in the source stream, protected and well vegetated catchment and low concentrations of nutrients in the surface layer. This is in direct contrast to the situation in the Fitzroy River.