Animal wastewater from dairy and swine farms can be effectively treated in constructed wetlands. To ensure long-term functionality, it is crucial to remove solids before treatment. Plants like cattails and bulrushes play a key role in wetlands by absorbing nutrients, providing surface area, and transporting oxygen. Marsh-pond-marsh designed wetlands can improve oxidation and nitrification. Wetlands naturally contain denitrifying bacteria that help break down nitrogen, but phosphorus removal may be limited. To enhance treatment efficiency, additional procedures promoting oxidation may be needed. Wetlands are also effective in reducing harmful pathogens in animal wastewater.