State of Idaho Department of Environmental Quality Manuals

State of Idaho Department of Environmental Quality Individual and Subsurface Sewage Disposal Systems Technical Guidance

This manual provides detailed technical guidance for the design, installation, operation, and maintenance of individual and subsurface sewage disposal systems in Idaho. It covers soil and groundwater evaluation, standard system design, alternative systems, and approved installers and components. The document is intended for professionals and property owners to ensure compliance with state regulations.

The manual includes sections on soil texture, separation guidelines, system types such as drainfields, composting toilets, and sand mounds, as well as requirements for inspections, maintenance, and monitoring. It also addresses property access, managed operation, and system failure protocols.

Covers: Soils and Groundwater · Standard Subsurface Disposal System Design · Alternative Systems · Approved Installers, Pumpers, and Components · Operation and Maintenance · Inspections and Monitoring