The effects of a number of factors on the rate of solution of oxygen in fresh and saline water were investigated experimentally to provide information about re-aeration in a polluted estuary.
It was shown that stirring the water at different speeds with impellers or forcing air streams of different velocities tangentially over the surface caused relatively gradual changes in the rates of solution, measured as exit coefficients, until the surface became visibly disturbed. Thereafter there was a much more rapid increase in rate of solution with increasing rate of stirring or wind velocity.
Increasing the height and frequency of stable progressive waves and the height of choppy waves generated mechanically in the water caused an approximately linear increase in rate of solution.
Under different conditions of surface agitation the rate of solution increased linearly with increasing temperatures in the range 0–35°. The temperature coefficients, defined as the increase in rate of solution expressed as a percentage of the value at 20°, per degree Centigrade increase in temperature had a mean value of 2.37.
Oil films on the surface of the water caused little effect until the thickness of the film exceeded 10−4 cm. A soluble surface contaminant, on the other hand, caused considerable reductions in the rate of solution, which increased with increasing concentration of the contaminant but which tended to a limiting value.