Indiana Code Title 16. Health § 16-41-25-7

Sec. 7. (a) After June 30, 2023, a county, city, or town ordinance may not adopt requirements, restrictions, or conditions concerning the:

of a residential onsite sewage system that are more stringent than the requirements, restrictions, and conditions of the rule of the state department concerning residential onsite sewage systems.  An ordinance that imposes requirements, restrictions, or conditions that are more stringent than the requirements, restrictions, and conditions of the state department's rule concerning residential onsite sewage systems is subject to invalidation under IC 16-19-3-27.8(e).

(b) After June 30, 2023, a local health department may not adopt requirements, restrictions, or conditions concerning the:

of a residential onsite sewage system that are more stringent than the requirements, restrictions, and conditions of the rule of the state department concerning residential onsite sewage systems.  After June 30, 2023, any requirements, restrictions, or conditions that are adopted by a local health department and that are more stringent than the requirements, restrictions, and conditions of the state department's rule concerning residential onsite sewage systems are void and unenforceable.