RP240 Constructed Wetlands
Recently, humans have become more aware of our technological limitations. Instead of trying to invent new solutions to our problems, we' re looking to the natural world for guidance. One pressing problem is our need for clean water. The solution to protecting our water resources may be the soggy areas of ground we often take for granted: wetlands.
Wetlands may not look spectacular, but they perform amazing feats. One of them is filtering and cleaning water. Dirty water enters a wetland, passes through its parts, and emerges cleaner on the other side! They' re like biological water filtration machines. Around the world, people are constructing wetlands instead of building huge, smelly tanks to purify their waste water. A wetland can clean waste water enough to allow it to safely reenter a clean water source.
Wetlands use mechanical and chemical processes to filter water. The first steps are mechanical: Dirty water runs through the stones and plant stems, and solid particles are trapped. They fall to the bottom to become soil. Then, the chemical processes. If the particles attach themselves to stones or stems, the bacteria growing there break them down into harmless nutrients. Often, plants use the dangerous fertilizer or chemical pollutants and in return, give off beneficial oxygen!
Dangerous parasites that travel in water can also be destroyed in wetlands. Flatworms and other parasites are eaten by animals in the wetland, killed through lack of oxygen, or destroyed by sunlight. Constructed wetlands are designed to hold water long enough for most parasites to be killed through one of these processes.
Wetlands do require some work. They must be maintained and monitored, and they can be affected by season changes. But for the most part, wetlands are cheap, environmentally friendly, and sustainable solutions to the problem of polluted water. And in addition to the work they do, they can be designed to be beautiful natural spaces for people to visit and enjoy.
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