A mixing criterion for turbid rivers

A criterion for the formation/destruction of thermal stratification in turbid rivers is developed and tested against an extensive data set in a weir pool on the Murrumbidgee River, Australia. The criterion estimates whether a river section would stratify or not, subject to a prescribed heat flux through the water surface and a prescribed river flow. It can be determined from readily accessible parameters, including solar radiation, turbidity, wind speed and river discharge. It is suggested that this simple mixing criterion be used as a flow management tool in a variety of water quality applications in rivers.