Indiana
The stormwater permit for construction in Indiana
Indiana runs its own NPDES programme, so a state issued construction general permit governs. Below is what our engine can say about it, and where we have not read that permit, what it will not say.
Governing permit
Construction Stormwater General Permit (CSGP), Permit INRA00000
- Issued by
- Indiana Department of Environmental Management (IDEM), Office of Water Quality
- Permit number
- INRA00000
- Version determined against
- as published by the state agency
- Effective
- 2021-12-18
- Expires
- 2026-12-17
Who may prepare the plan
No preparer credential foundNo preparer credential was found for Indiana. On what we have verified, a generated plan can be adopted by the operator without a credentialed signature. Local ordinances can still be stricter than state law.
No preparer credential found in the reviewed sources. Not exhaustively verified; confirm with the state agency and any local ordinance.
No permit section cited. Confirm this with your permitting authority.
Does a site in Indiana need coverage
Worked for a one acre site as a reference point. Change the acreage in the tool below and the answer, and its reasoning, change with it.
Coverage
Permit coverage required
The project disturbs 1 acres, at or above the 1 acre threshold, so it needs permit coverage.
Determined against dataset version 2026-07-19.
Read these before you act on the answer
- Requirements below are what we have read and cited directly from Construction Stormwater General Permit (CSGP), Permit INRA00000, not the federal CGP. A category we have not yet transcribed from this permit is omitted here rather than assumed to match EPA's rule.
- No numeric turbidity/pH/TSS effluent benchmarks were found anywhere in the permit text; Indiana's CSGP relies entirely on narrative, BMP-based performance standards (Section 3.0), so numericLimitsAndBenchmarks is omitted. No explicit day-count deadline for NOT submission was found -- Section 6.4 lists conditions precedent rather than a fixed number of days after project completion, so deadline.not.submission is omitted. No inspection-frequency provision equivalent to federal's sensitive/impaired waters increased-frequency trigger was found, so inspection.increased.sensitiveWaters is omitted. Indiana's climate is not arid/semi-arid, so inspection.reduced.aridSemiAridDrought is genuinely inapplicable and omitted. Indiana's stabilization completion rule (14 days after initiation, flat) is NOT acreage-tiered like federal Table 2, so it was modeled under a new state.in.* id.
- No preparer credential was found for Indiana. On what we have verified, a generated plan can be adopted by the operator without a credentialed signature. Local ordinances can still be stricter than state law.
- Basinwise does not perform the physical site inspections the permit requires. Those must be carried out on site by a qualified person.
How this answer was reached, step by step
- 1
Coverage threshold
The project disturbs 1 acres, at or above the 1 acre threshold, so it needs permit coverage.
- 2
Permitting authority
Indiana. The state runs its own programme under INRA00000.
- 3
Preparer credential
No preparer credential was found for Indiana. On what we have verified, a generated plan can be adopted by the operator without a credentialed signature. Local ordinances can still be stricter than state law.
What to do next
- 1. Confirm the governing permit. Read Construction Stormwater General Permit (CSGP), Permit INRA00000 directly. It is linked above, and it is the document an inspector will hold you to. Indiana Department of Environmental Management (IDEM), Office of Water Quality
- 2. Settle the preparer question before you draft. Getting this wrong costs a redraft at best. The detail is on the credential page for this state. Preparer credential in Indiana
- 3. Screen the site. Run the real acreage and receiving water facts through the tool below. You get the inspection frequency, the stabilisation deadlines and the filing path with the permit section behind each.
- 4. Read the requirements in full. SWPPP requirements in Indiana
Screen a Indiana site now
Runs in your browser. Nothing about the site is transmitted.
What people ask about the Indiana construction stormwater permit
Do I need a stormwater permit for a construction site in Indiana?
Permit coverage is triggered at one acre of land disturbance, and below one acre if the project is part of a larger common plan of development or sale that will ultimately disturb an acre or more. The project disturbs 1 acres, at or above the 1 acre threshold, so it needs permit coverage.
Who issues the construction stormwater permit in Indiana?
Indiana Department of Environmental Management (IDEM), Office of Water Quality issues Construction Stormwater General Permit (CSGP), Permit INRA00000.
Does Indiana require a qualified preparer for the plan?
No preparer credential was found for Indiana. On what we have verified, a generated plan can be adopted by the operator without a credentialed signature. Local ordinances can still be stricter than state law.
Keep the record Indiana will ask you for
The screening is free. Holding the written plan and the retained inspection log is what the permit actually demands.