When a Permit is Required
A permit is required for the installation, alteration, expansion, or repair of any Onsite Wastewater Treatment System (OWTS) with the following exceptions:
- Changing and cleaning filters
- Adjusting head pressures
- Replacing pumps, aerators, and blowers with like equipment
When in doubt, contact the Division of Building and Code Enforcement at 636-949-7345 or firstname.lastname@example.org.
Where a Permit is Required
The St. Charles County Division of Building and Code Enforcement issues permits in unincorporated St. Charles County and cities in which we contract.
To assist in determining which jurisdiction your project is located and whether St. Charles County issues permits, please use the Permit Lookup Tool.