Wetlands: A Natural Water Treatment Alternative
The balance between industry and nature preservation is an issue that mankind constantly struggles with. Wastewater from agricultural, municipal, and industrial sources seep into natural habitats and effectively poison wildlife. This issue has historically been dealt with by the construction of water treatment facilities, but many of the facilities already installed require upgrading to deal with the ever increasing pollution problem.
The implementation of natural methods of pollution control has been an area of considerable interest for naturalists everywhere. Wetland plants cleans stagnant water while also providing a habitat for wildlife to thrive in. In most cases, the cost to implement a wetland habitat is only slightly more expensive than constructing a water treatment center.
The creation of wildlife habitats and the aesthetic of wetlands are readily apparent benefits, but there are also less obvious benefits. Vegetative root systems hold soil in place and prevent flooding and receding shorelines. These hazards can be particularly dangerous when a community has settled near a shore. Flooding can cause major problems for an area's agriculture, especially because the floodwaters may contain pollutants.
The way that wetland plants cleans stagnant water is through decomposition. A variety of microorganisms live on the surface of the wetland plant's bark, roots, and leaves. These bacteria and fungi feed on the biodegradable material in the wastewater and produce carbon-dioxide (CO2) and water as a result. The wetland plants feed on the CO2 and emit oxygen (O2), which the bacteria then feed on, and the cycle continues. It's important to note that this process is only well-suited for biodegradable wastes and relatively mild pollutants. Harsher chemicals and plastics could potentially do harm to the wetlands system of filtration. It's for this reason that the wetlands water treatment system is best for municipal and agricultural waters.
There are two different systems for managing the inflow of waste water. Free water surface systems allow contact between the wastewater and the atmosphere. This system requires minimal engineering, but may emit unpleasant smells. The alternative is the subsurface flow system. These installations use a system of underground pipes to direct the wastewater under the wetlands environment. Subsurface flow systems mitigate the issue of smell, but require a greater engineering cost.