There are many important aspects of a wetland that must be considered in efforts to maintain your wetland at peak effectiveness. Operational concerns consist of the following steps from the wetland checklist:
For the first few years of operation, regular samples (every two weeks) should be collected from the inlet and outlet of the wetland - potentially even where water is dispersed from the property. These samples should be tested for nitrate, phosphate, and pesticide concentrations.
Many nurseries find that the inlet area samples from the wetland indicate overfertilization of their production area. Thus, cost savings can be realized in decreased fertilization. After the first few years, inlet sampling may no longer be needed.
Outlet sampling helps with water quality control over the life of the wetland and should be continued always to ensure standard and regulation adherence.
Wetland maintenance is exceedingly simple. There are only a few things that must be done to keep the wetland in good working order. Remove willows (Salix sp.) from the wetland at regular intervals. This can be done manually where plants are small or through carefully targeted chemical means when larger plants are being controlled. If willow trees are allowed to gain sufficient size, their roots can penetrate the hard pan beneath the wetland causing it to leak and not process as efficiently. In extreme circumstances, hard pan cracking can lead to ground water contamination.
While constructed wetlands can last for decades, they will not last forever. Nutrients retained in wetlands may reach high enough levels that additional measures are required to retain efficacy. Excessive sediment accumulation may fill wetlands - requiring removal efforts. If large levels of pesticides are collected in the wetland, they may become toxic over time. Many wetlands, however, have been operating continually for more than 20 years. Despite their finite life expectancy, wetlands provide efficient water treatment for many years.