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{{topic header| default.png | Constructed wetlands}} | {{topic header| default.png | Constructed wetlands}} | ||
Constructed wetlands (CW), or artificial wetlands, are engineered wetland ecosystems that have been designed and constructed to use natural wetland processes for the removal of pollutants. These systems mimic marshes with aquatic plants, soil, and associated microorganisms but take advantage of a controlled environment to treat wastewater. Wetlands have shown the ability to meet this goal in an aesthetic, sustainable, and economical manner<ref>Kivaisi, A. K. (2001). The potential for constructed wetlands for wastewater treatment and reuse in developing countries: a review. Ecological Engineering, 16(4), 545–560. doi: http://dx.doi.org/10.1016/S0j925-8574(00)00113-0 | |||
</ref>. However, they require large areas of land, consistent maintenance, and technical operational knowledge. | |||
The | ==History== | ||
Natural wetlands have been used as wastewater discharge sites since the beginning of sewage collection. Once their ability to treat water was discovered, as early as the 1950s, early research efforts to use and assess constructed wetlands were begun.(23)Dr. Kathe Seidel at the Max Plankck Institute in Plon, Germany, tested the ability of bulrushes to treat wastewater. Her discoveries led to the first subsurface CW for municipal wastewater treatment in 1974 in the community of Liebenburg-Othfresen, Germany. The first free water surface CW was implemented in The Netherlands in 1967. This system had a star-shaped layout and was called a "planted sewage farm". During the later 20th century, the popularity of CWs grew in Europe and North America. CWs have traditionally been used to treat sewage but, since the late 1980s, have been used to treat a variety of wastewater types such as domestic wastewater, mining and industrial wastewaters, agricultural wastewaters, landfill leachate, stormwater, and runoff.(3)(9) In developing communities, they can be used to treat greywater or used as a secondary treatment for domestic sewage. The main wastewater treatment goal in developing countries is protection of public health through control of pathogens in order to prevent transmission of waterborne diseases and eutrophication of surface waters(22). | |||
==Design== | |||
==Theory== | |||
==Construction== | |||
==Operation and Maintenance== | |||
==Evaluation == | |||
==Impacts== | |||
==Dissemination== | |||
==Re-Design== | |||
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* [[Wikipedia:Constructed wetlands]] | * [[Wikipedia:Constructed wetlands]] | ||
==References== | |||
{{Reflist}} | |||
== External links == | == External links == | ||
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[[Category:Sanitation]] | [[Category:Sanitation]] | ||
[[Category:Constructed wetlands| ]] | [[Category:Constructed wetlands| ]] | ||
Revision as of 03:00, 18 December 2012
Constructed wetlands (CW), or artificial wetlands, are engineered wetland ecosystems that have been designed and constructed to use natural wetland processes for the removal of pollutants. These systems mimic marshes with aquatic plants, soil, and associated microorganisms but take advantage of a controlled environment to treat wastewater. Wetlands have shown the ability to meet this goal in an aesthetic, sustainable, and economical manner[1]. However, they require large areas of land, consistent maintenance, and technical operational knowledge.
History
Natural wetlands have been used as wastewater discharge sites since the beginning of sewage collection. Once their ability to treat water was discovered, as early as the 1950s, early research efforts to use and assess constructed wetlands were begun.(23)Dr. Kathe Seidel at the Max Plankck Institute in Plon, Germany, tested the ability of bulrushes to treat wastewater. Her discoveries led to the first subsurface CW for municipal wastewater treatment in 1974 in the community of Liebenburg-Othfresen, Germany. The first free water surface CW was implemented in The Netherlands in 1967. This system had a star-shaped layout and was called a "planted sewage farm". During the later 20th century, the popularity of CWs grew in Europe and North America. CWs have traditionally been used to treat sewage but, since the late 1980s, have been used to treat a variety of wastewater types such as domestic wastewater, mining and industrial wastewaters, agricultural wastewaters, landfill leachate, stormwater, and runoff.(3)(9) In developing communities, they can be used to treat greywater or used as a secondary treatment for domestic sewage. The main wastewater treatment goal in developing countries is protection of public health through control of pathogens in order to prevent transmission of waterborne diseases and eutrophication of surface waters(22).
Design
Theory
Construction
Operation and Maintenance
Evaluation
Impacts
Dissemination
Re-Design
| Constituent | Free-Water Surface | Subsurface Flow |
|---|---|---|
| BOD | 93% | 93% |
| TSS | 91% | 72% |
| Nitrogen | 88% | 94% |
| Phosphorus | 53% | 65% |
How to Size a Free Water Surface Wetland using Kadlec and Knight model
1. Determine the limiting effluent requirements for BOD, nitrogen, or pathogens.
2. Calculate the surface area for BOD, nitrogen, or pathogens using the following equation. The largest surface area will be the control.
A is the wetland area required (hectares)
Suggested projects and requested content
- How to determine the necessary size and design of a constructed wetland? (Start a how-to: How to design and build a constructed wetland.
Interwiki links
References
External links
- Constructed wetlands by Bruce Lesikar (Extension Agricultural Engineering Specialist, the Texas A&M University System)
- ↑ Kivaisi, A. K. (2001). The potential for constructed wetlands for wastewater treatment and reuse in developing countries: a review. Ecological Engineering, 16(4), 545–560. doi: http://dx.doi.org/10.1016/S0j925-8574(00)00113-0