Is it required to install a new septic tank in series if two tanks are needed?

The requirement to install a new septic tank in series when two tanks are needed is generally a common practice in septic system design. When two tanks are installed in series, the first tank acts as the primary treatment unit, where solids settle and anaerobic digestion occurs. The second tank serves as a post-treatment unit that further clarifies the effluent before it moves into the drain field.

This configuration can enhance the treatment efficiency and improve the overall performance of the system, particularly in dealing with larger volumes of wastewater or when the soil conditions may not be ideal for a one-tank system. In many regulatory frameworks and best practice guidelines for septic systems, the installation of two tanks in series is recommended to ensure adequate treatment and reduce the risk of system failure.

While local regulations can vary, the principle of using two tanks in series is rooted in sound engineering practices and is often required for compliance with health and environmental standards.