In the Peace River Region, aeration is generally practiced mainly in winter when dugout oxygen levels drop to near zero resulting in taste and odour problems. The traditional aeration method used is air injection in the region of the water intake, the air coming out the end of tubing connected to a compressor. Generally the tubing used is nominally 1.27 cm inside diameter. This type of aeration results in a large area of open water, a polynya, around the site of air injection. Anoxic conditions may occur both in summer and in winter but they are most pronounced in winter when dugouts may be ice covered for many months.
Anoxic conditions result in a shift from oxidizing to reducing environments in dugouts.
Aeration serves to both strip out these gases and to create an oxidizing environment which prevents further formation of the offending gases. Mechanical aeration devices in the form of pumps which float on the surface have also been used as aeration devices to prevent winterkill. In this study we set out to test the hypothesis that effective aeration required complete water circulation through out the dugout. We also hypothesized that the depth to which water is circulated will be related to the location of the surface aerator or diffuser in the dugout. This study was conducted on farm dugouts within a 10 km radius of the town of Falher, Alberta.