What regulation must a septic tank comply with regarding its design?

A septic tank must comply with the Washington State Septic System Regulations, which are specifically designed to ensure the safe and efficient management of wastewater in the state. These regulations cover various aspects of septic tank design, installation, maintenance, and operation, ensuring that public health and environmental protection standards are met.

The Washington State Septic System Regulations take into account local soil conditions, groundwater levels, and existing infrastructure, making them highly relevant for septic systems in that region. They dictate requirements such as tank size, materials, and installation methods, which are crucial for the effective treatment of sewage and prevention of contamination.

The other options, while they may be relevant in different contexts, do not specifically address the state-specific requirements for septic systems in Washington. Federal guidelines may establish broader standards, but state regulations are essential for compliance at the local level. Similarly, local building codes may pertain to construction practices, yet they operate in conjunction with the state regulations, which provide critical details unique to septic system design and function.