Lagoons · Common Lagoon Problems
Why Is Duckweed a Problem on a Lagoon?
Duckweed and similar small floating plants can spread across quiet lagoon water. A thick cover blocks sunlight, so algae make less oxygen. It also limits oxygen transfer from the air. Material can rot below the mat and add to low oxygen or odor.
Growth often starts in sheltered spots with little wind or circulation. Check corners, baffles, banks, and outlet areas. Record how much of the surface is covered and whether the cover is growing. Tell rooted shoreline plants apart from plants floating on the water.
Wind and water movement help break up duckweed. Small patches are easier to deal with than a full cover, so act early.
Control must follow the plant's approved procedures and any environmental limits. Removed plants must be handled properly. Herbicides or other chemicals need authorization, correct use, site procedures, and the SDS.
Key point: Floating plant cover can block the light and oxygen exchange a lagoon needs.
Keep learning
Lagoons and Small Wastewater Plants
This page comes from the course. It covers facultative and aerated lagoons, monitoring, lagoon problems, berms and liners, package plants, permits and safe work, one step at a time, with short knowledge checks and a certificate of completion.
Take the course