Before the CW can be used, it is best if the plants are well-developed before they encounter the wastewater effluent, so that they have a strong foundation and greater stress tolerance. <ref> Vymazal, J. (Ed.). (2010). Water and Nutrient Management in Natural and Constructed Wetlands. Springer.</ref> Also, the water level should be appropriate for developing plants. Too much water will prevent oxygen from reaching the plant roots. A few centimeters of water should be in the basin at all times. <ref name = "Purdue">Purdue University. (1998). Individual residence wastewater wetland construction in Indiana. Retrieved from https://engineering.purdue.edu/~frankenb/NU-prowd/buildcw.htm</ref> The water level can be raised gradually to the design operating level. A well-constructed FWS wetland will take around six weeks before wastewater should be routed into it, and the vegetation will be fully developed around the second growing season. Right after construction is the point at which the most maintenance is required. Large areas where plants fail to grow should be re-planted, and intended free surface areas should be kept clear through harvesting. Once the wetland has reached equilibrium, the only real maintenance tasks required are water level and quality monitoring, erosion control, and berm maintenance. In the established system, vegetation should cover a bit more than 50% of the surface <ref name = "Vymazal">.