HYPOLIMNETIC AERATION: AN OVERVIEW.

Hypolimnetic aerators are now being widely used throughout Europe and are beginning to appear in small and medium sized eutrophic lakes in temperate North America. This activity has produced approximately 42 published reports dealing with experiments conducted at 16 lakes. Taken together, the evidence from these experiments suggests that well designed aerators do not cause significant destratification or warming of hypolimnetic water, but do result in measurable increases in hypolimnetic oxygen concentration and decreases in dissolved hydrogen sulfide, methane and ammonia. The aggregate practical and experimental experience suggests that well designed hypolimnetic aeration systems yield measurable improvements in water quality and will almost certainly prove to be one of the major methods used for future in situ lake restoration.