Indiana NPDES Permits
In Indiana, EPA has delegated authority to issue NPDES permits to the Indiana Department of Environmental Management.
NPDES Petition for Program Withdrawal in Indiana
Pretreatment: EPA and authorized NPDES state pretreatment programs approve local municipalities to perform permitting, administrative, and enforcement tasks for discharges into the municipalities. This spreadsheet explains the limits for Indiana. Region 5 Pretreatment Limit Spreadsheet Illinois/Indiana(101 K, Nov. 2018) Information about the National Pretreatment Program.
For state-issued permits, visit Indiana's Wastewater Permitting Program Exit