An aerated lagoon (or aerated pond) is a simple wastewater treatment system consisting of a pond with artificial aeration to promote the biological oxidation of wastewaters.

There are many other aerobic biological processes for treatment of wastewaters, for example activated sludge, trickling filters, rotating biological contactors and bio-filters. They all have in common the use of oxygen (or air) and microbial action to reduce the pollutants in wastewaters.

Advantages:

• Lagoon systems can be cost effective to design and construct in areas where land is inexpensive.

• They use less energy than most waste water treatment method

• They are simple to operate & maintain and generally requires part time staff.

• They can handle intermittent use and shock loadings better than many system.

Disadvantages:

• Lagoon system requires more land than other treatment method.

• They are less efficient in cold climates and may require additional land or longer detention time in these areas.

• Unless they properly maintain, lagoon can providing a breeding area for mosquito and other insect.