MI HB4479

Establishes comprehensive state regulatory framework for onsite wastewater treatment systems, replacing piecemeal local regulations and creating statewide code administered by Department of Environment, Great Lakes, and Energy.

Requires owners to conduct inspections of onsite wastewater treatment systems at least once every 5 years, with inspectors conducting detailed assessments of septic tanks, dispersal systems, and potential failures starting January 1, 2026.

Mandates local health departments adopt qualified staff requirements including 4-year bachelor's degree in environmental or related field, minimum 8 hours training in soil classification, and supervised field evaluations before independent work.

Prohibits new point-of-sale inspection ordinances for septic systems and requires local units of government to phase out or repeal existing ordinances within 1 year; allows counties 7 years to comply.

Requires proprietary wastewater treatment products to register with the state for $3,000 fee by January 1, 2026, with 5-year validity period; establishes registered inspector program requiring training and education standards with $180 application fee.