Stabilization pond

Stabilization ponds (also called lagoons or waste stabilization ponds) use a natural process for wastewater treatment that employs a combination of macrophytic plants, substrates and microorganisms in a more or less artificial pond to treat wastewater. The technique is frequently used to treat municipal wastewater, industrial effluent, municipal run-off or stormwater. After treatment, the effluent may be returned to surface water or reused as irrigation water (or reclaimed water) if the effluent quality is high enough

Stabilization ponds are commonly used for wastewater treatment in developing countries. Types of treatment ponds include settling basin, anaerobic lagoons, facultative pond and aerated lagoons.

Wastewater Stabilisation Ponds is the collective term for a system of ponds used in wastewater treatment, including:

Stabilization ponds consist of man-made basins comprising a single or several series of anaerobic, facultative or maturation ponds. The primary treatment takes place in the anaerobic pond, which is mainly designed for removing suspended solids, and some of the soluble element of organic matter (BOD). During the secondary stage in the facultative pond most of the remaining BOD is removed through the coordinated activity of algae and heterotrophic bacteria. The main function of the tertiary treatment in the maturation pond is the removal of pathogens, although it also assists in nutrient reduction (i.e. nitrogen).

A study of ten stabilization ponds in Honduras has shown that they were effective in removing helminth eggs, a pathogen, from the effluent and to satisfy the World Health Organization microbiological guidelines for Category B irrigation with wastewater effluent. However, sludge from all ponds was heavily contaminated with helminth eggs.

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