During my research I found that to capture the maximum amount of nutrients in the type of wetland that we are building (Stormwater Wetland) some key features are needed to succeed. One of these features is that the wetland must be designed and shaped in such a manner that the surface area of the wetland that is below the water surface is maximized. The “catchment area” from which the nutrient rich water will come from is also an important aspect to take into consideration when calculating the surface area of the wetland.
Another key feature is that the flow paths for the water that goes through the wetland should be as long as possible. This is in part because the longer the time that the nutrient rich water stays in the wetland, the more the nutrients will be able to settle in the wetland bottom forming sludge, or will be absorbed by the different types organisms (plants and microorganisms) living in the wetland. Another parameter to take into consideration when building wetlands, is that its design should include different depths across its structure. The different depths change (slow down) the speed at which water flows through the wetland and also provide different types substrates for different nutrient absorbing species of plants and microorganisms (some aerobic and others anaerobic), to establish themselves in different zones of the wetland. All the previously mentioned features provide the foundations for a resilient wetland ecosystem to thrive, maximizing the absorption of nutrients coming from runoff waters.
To complete the planning of Västankvarn Wetland Project, further research needs to be done concerning the soil type and permeability in both areas where each wetland is intended to be constructed. This will be of crucial importance for selecting the plants that will be used to settle in the wetland ecosystem and this will
also tell us if the submerged contours of the wetland will need to be covered with a special material to help the wetland retain its water. The inlets and outlets construction types for both wetlands will need to be further discussed with experienced specialists to make sure they are build in a proper manner and the wetlands achieve the optimal results.