Final Comment Period for Indiana Stormwater Permit
In September 2024, the Indiana Department of Environmental Management (IDEM) issued a draft Industrial Stormwater General Permit (ISGP), which is open for public comment until November 19, 2024. Upon completion of the public notice period the new permit is expected to go into effect in 2025. The new permit requirements will be more stringent in terms of sampling frequency, pollutant benchmarks, inspections, and corrective actions.
For a new facility, within 30 days prior to the occurrence of any discharge a new permit application Notice of Intent (NOI) must be submitted. For facilities that have existing permit coverage, within 180 days following the effective date of the new permit the facility will need to take one of the following actions:
Submit a new NOI
Request to terminate permit coverage;
Notify IDEM of eligibility for an exclusion from permit coverage;
Submit an application for an individual permit.
All permitted facilities are required to continue to meet the conditions of the current Indiana Permit (as defined in 327 IAC 15-6) including sampling and inspection requirements until the new ISGP permit is issued sometime in 2025. If your current permit coverage is set to expire before the new ISGP permit is issued you still need to submit a renewal NOI to maintain that permit coverage.
We understand the new upcoming changes to the Indiana stormwater permit may feel daunting.
If you’d like to be informed of the finalization of these regulation and tips for compliance, please drop your email below, and we will be in touch. Feel free to contact us if you’d like
Upcoming Changes to Indiana Stormwater Permits
In alignment with other states and Federal permit guidelines, Indiana is making some big changes to its Stormwater General Permit. This draft permit is currently in public notice review until November 19, 2024. Upon completion of the public notice period, IDEM will be working to finalize the new permit early in 2025. A key change to the permit is the addition of “subsectors” based on industry SIC codes, creating variable requirements for facilities in differing industries.
We understand these changes may feel daunting. If you have any questions or would like assistance with stormwater reporting management, we’re here to help. Our turnkey services ensure you’re up to date with the latest regulations, submission details, and reporting deadlines.
If you’d like to be informed of the finalization of these regulation and tips for compliance, please drop your email below, and we will be in touch.
Here’s a look at high level changes you’ll see in the draft:
Changes to Inspection Requirements
Quarterly Routine Facility Inspections are still required, but now required to have at least once per year done during a period where stormwater discharge is occurring (i.e. when it’s raining)
Added Quarterly Visual Assessments for each outfall even if they are substantially similar.
Changes to Annual Report
First annual report due within 365 days of effective date of permit coverage. The annual report for years 2 through 5 is due within 365 days of the last report submitted.
Annual reports must now include summary of facility inspections, visual assessments, confirmation SWPPP is updated, confirmation of impaired waterbody review, sampling information and any correction actions.
Additional Changes
Non-stormwater discharges allowed under the permit,
Minor changes to Facility Layout requirements
Additions items to include in SWPPP
Changes to Notice of Intent
Annual fee structure has changed.
Lots of additional information is now needed as part of the NOI and they must be submitted electronically through the IDEM Regulatory Services Portal (RSP).
Within 180 days of the effective date of the new permit facilities must submit a new NOI, request a termination of permit coverage, request no exposure exclusion, or apply for individual permit. Subsequent renewals 5 years later are still due 90 days before general permit expires.
Changes to Stormwater Monitoring Requirements
All facilities must conduct stormwater monitoring for three “indicator benchmark parameters” (i.e. pH, Total Suspended Solids, Chemical Oxygen Demand)
Additional monitoring requirements is broken down by subsector and/or waterbody
pH measurement must still be taken at the time the grab sample is taken using a pH meter. Calibration records of the pH meter must be kept with the SWPPP (cannot rely on a lab to provide/maintain these records).
Changes to Stormwater Monitoring Reports
Discharge Monitoring Reports must be submitted online in NetDMR system
To stay up-to-date on these changes, drop your email address in the form above!