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Constructed
Wetlands... |
publication of the National Small Flows clearinghouse at West Virginia University, Morgantown, WV.What type of image first come to mind when you think about waste water treatment?
Chances are you wouldn’t immediately picture your wastewater system as a good place to watch a sunrise or catch a glimpse of a moose, a crane, or other exotic wildlife. But for the growing number of small communities and individual homes using constructed wetland systems, effective wastewater treatment can be achieved without disturbing the natural beauty and serenity of rural areas.A Low-Cost, Low-Energy Option
How Wetlands are Used to Treat Wastewater
It has long been known that natural wetland areas (such as marshes, swamps, and bogs, for example) play an important role in protecting water quality.
Constructed or artificial wetland systems mimic the treatment that occurs in natural wetlands by relying on plants and a combination of naturally occurring biological, chemical, and physical processes to remove pollutants from water.
In fact, some constructed wetland system designs closely resemble natural wetlands and even provide additional habitat area for the many birds, animals, and insects that thrive in wetland environments. But because constructed wetland systems are designed specifically for wastewater treatment, they work more efficiently than natural wetlands.
Constructed wetlands can treat wastewater generated by a variety of sources. One of their more common uses is to provide additional or advanced treatment of wastewater from homes, business sites, and entire communities. This means they are used by homes and communities to treat wastewater that has already had most solid materials removed from it through some type of primary or secondary treatment (for example, in a septic tank, lagoon, aerobic unit, or treatment plant).
While the exact roles of some of the natural treatment processes in wetlands are still not completely understood, enough information currently is available for experienced wastewater consultants to design systems that perform reliably and meet environmental treatment standards. Communities should hire a consultant or engineering firm that has specific experience designing wetland systems.
A Low-Cost, Low-Energy Option
Constructed wetland systems have only been used for wastewater treatment since the 1970s, which makes them a relatively new wastewater treatment technology. However, interest in their use has quickly become widespread.
For example, in a recent survey of Pipeline readers, constructed wetland technology was recommended most frequently as a topic for future articles.
Wetland systems also are a popular subject with the many community leaders, health officials, and homeowners who call the National Small Flows Clearinghouse’s (NSFC) technical assistance hotline (800-624-8301 or 304-293-4191).
One of the reasons that people are curious about constructed wetlands is the low cost associated with these systems. Compared to many other treatment methods, wetland systems are inexpensive to construct and maintain, and operating costs are low because energy is not required to provide treatment.
This article offers a basic overview about constructed wetlands. How they work, and some of the advantages and disadvantages.
This is the first of three articles on constructed wetlands. It has
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