Studies were made of mixing in relation to thermal pollution. The flow pattern and temperature distribution from the discharge of a submerged two-dimensional turbulent hot water jet into a large still reservoir of cooler water was studied. Barriers were then placed around the point of exhaust to further confine the warmer water. Methods for the mixing of a thermally stratified flow in a channel were investigated for the reuse of the thermally stratified water near the jet exhaust. This can be applied in any closed circuit condenser intake in order to avoid local hot water regions detrimental to condenser operation. The effect on thermal mixing of a stratified channel flow resulting from the introduction of rigid barriers normal to the flow is considered.