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Wetland sewage systems

Natural wetland systems perform many functions that are beneficial to both humans and wildlife. One of their most important functions is water filtration.

As water flows through a wetland it is slowed down and suspended solids become trapped by vegetation and settle out. Other pollutants are transformed to less soluble forms taken up by plants or become inactive. Wetland plants also foster the necessary conditions for microorganisms to live there. Through a series of biological processes these microorganisms process, transform and filter  pollutants from the water.

Constructed wetlands are an ecological low-cost solution for effective sewage and water waste treatment that mimic a natural wetland. They can treat both blackwater (water containing fecal matter with or without urine) and/or greywater (laundry, dishwashing and bathing water). Wetlands are constructed by excavating, backfilling, grading, diking and installing water control structures to establish hydraulic flow patterns. Wetland vegetation is planted and also allowed to establish naturally.