Effect of Wind and Rain on Surface Reaeration

Over the years, considerable research has been conducted on the subject of surface reaeration in rivers and estuaries. As a result much information is now available to determine the surface reaeration coefficient in these bodies of water. In contrast, not much is yet known about the magnitude of this coefficient in lakes and lagoons. Some studies indicate that wind action is important in establishing the rate of oxygen transfer across the surface of a lake or lagoon. In addition, it appears that the effect of rainfall may be important in reaeration in some lakes. In the present study, analyses were made of the effects of wind and rain on reaeration. Expressions were developed relating the rate and power of a rainfall to the surface reaeration coefficient. It was also determined that the direct addition of oxygen from oxygen-saturated raindrops can be an important factor in reaeration.