Extensive Systems | Advantages | Disadvantages |
Natural Lagoons | Low operational cost and little maintenance. Suitable for high pollutant loads. Good reduction of pathogens and organic matter. | Requires a large area. Sensitive to seasonal and climatic variations. |
Horizontal flow constructed wetlands | Effective in treating BOD5, COD, nitrates, phosphates. Habitat for biodiversity. Low operational and maintenance costs. | Requires significant area. Less effective for high coliform loads. Sensitive to seasonal variations. |
Vertical flow constructed wetlands | Effective in treating organic pollutants and nutrients. Low maintenance. Aesthetically pleasing. | Requires certain area. May require pretreatment for very high loads. |
Infiltration Wells | Good for BOD5 reduction and solids filtration. Recharges groundwater. | Less effective for nutrients and pathogens. Risk of groundwater contamination. |
Biological rotating contactors | Effective for reducing BOD5 and suspended solids. Compact footprint. | Requires mechanical equipment. Less effective for nutrient treatment. |