Anaerobic Lagoon

Constructed pond-like body of water or basin designed to receive, hold and treat wastewater for a predetermined period of time in the absence of oxygen. Anaerobic lagoons are most often used to treat animal wastes from dairies and pig farms, commercial or industrial wastes or as the first treatment step in systems using two or more lagoons in a series. Anaerobic lagoons are designed to hold and treat wastewater from 20 to 50 days, are relatively deep (e.g., 8-15 feet) and work much like septic tanks. Solids separate and settle into layers, the top scum layer keeping out air to create anaerobic conditions and the bottom sludge layer eventually accumulating and requiring periodic removal. Also as with a septic tank, wastewater from an anaerobic lagoon always requires further treatment (e.g., in a series of lagoons). Anaerobic lagoons are often covered with a floating cover whereas methane gases can be collected and recycled as a fuel source. <