What is the maximum effluent concentration for BOD₅ and TSS that treatment ponds can typically achieve?

Treatment ponds, also known as lagoons or stabilization ponds, are designed to treat wastewater through biological processes and natural sedimentation. They are effective in reducing the concentrations of biochemical oxygen demand (BOD₅) and total suspended solids (TSS) in the effluent.

The maximum effluent concentration for both BOD₅ and TSS that treatment ponds can typically achieve is around 30 mg/L. This value is recognized as a threshold for effective treatment given the design, operational practices, and retention times associated with these systems. By maintaining optimal conditions such as sunlight, temperature, and microbial activity, these ponds can effectively reduce organic matter and suspended solids in the wastewater.

Achieving lower concentrations, such as 20 mg/L, is challenging for typical treatment ponds under many conditions, as it often requires advanced treatment processes or longer retention times. While values like 40 mg/L or 50 mg/L could be achievable under specific scenarios, they do not represent the typical maximum capacities of these systems. Thus, 30 mg/L stands out as the standard benchmark for effective treatment in these types of systems.