Firstly, Waste water management  is a process used to convert

wastewater into an effluent, that can be returned to water-cycle

with minimal impact on the environment.

Constructed Wetlands (CW) are artificial wastewater 

which have been planted with aquatic plants and which depends upon natural microbial, biological, physical and chemical processes to treat waste-water. 

CW is also known as Reed beds, soil infiltration beds, engineered

wetlands. CW is for the treatment  of municipal or industrial wastewater, grey water or storm-water  runoff.

Constructed Wetlands in Nepal

            How does wetland improve water quality?

• Settling of suspended particular matter.
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• Filtration and chemical precipitation through contact of water with substrate.
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• Chemical transformation.
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• Adsorption and ion exchange on the surface of plants, substrate,
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•  sediment and litter.
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• Breakdown and transformation of pollutants by microorganisms
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• and plants.
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• Uptake and transformation of nutrients by microorganisms.
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• Predation and natural die-off of pathogens.
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• Less expensive to build than other treatment option.
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• Operation and maintenance expenses are low.( energy and 
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•  supplies)
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• Require only periodic, rather than continuous, on-site labor.
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• Able to tolerate fluctuations in flow.
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• Facilitate water reuse and recycle