What is a lake-water circulation system and how does it work?
There are two types of lake-water circulation systems: lake mixers, which destratify a lake, disturbing stagnant water; and selective layer treatments, which focus on oxygenating just the bottom or middle layer of the lake without mixing with the surface. Both systems aim to reduce nutrient levels in the water, particularly phosphorus and ammonia, in part by increasing oxygen levels. Lake mixers are occasionally used to churn the water so algae blooms can’t take hold.
Lake mixers, including bubblers, propellers, and jets, mix cold lower water with warmer upper water. These systems add oxygen and reduce algae growth by increasing the water’s contact with air, and need to be customized to your lake. Although cheaper than selective layer treatments, they may adversely affect fish and zooplankton habitats in deeper lakes and, in some cases, can actually promote growth of algae by warming the lake and releasing additional nutrients from the bottom.
Before installing either system, you’ll need permits from various government bodies, depending on the scale of your remediation efforts.