SW

Stormwater Directory

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Compare state-level permit requirements side-by-side (up to 4 states)

IN(3 more)

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Field
IN
Indiana
NPDES ProgramState-Delegated
Permitting AgencyIndiana Department of Environmental Management (IDEM)
Permit NameNPDES Construction Stormwater General Permit (Rule 5 / Permit INR100000)
Construction Threshold≥ 1 acre of land disturbance; < 1 acre if part of a larger common plan of development or sale
NOI Lead TimeNOI must be submitted and approved before earth-disturbing activities begin; no fixed calendar lead time is prescribed, but IDEM review typically takes several business days
Application MethodOnline via IDEM's myidem.in.gov portal (electronic NOI submission); paper NOI also accepted but online is preferred
Permit Fee$100 per NOI filing (flat fee); no acreage-based scaling
SWPPP RequiredYes
PE Certification RequiredNo
SWPPP Template AvailableYes
Inspection FrequencyAt least every 7 days and within 24 hours after a storm event producing ≥ 0.5 inches of rainfall in a 24-hour period; frequency may be reduced to every 14 days when the entire site is temporarily stabilized or runoff is unlikely due to winter conditions
Inspector QualificationInspections must be conducted by a qualified inspector who is knowledgeable about the permit requirements and BMP implementation; Indiana does not mandate a specific state-issued certification, but IDEM recommends Certified Inspector of Sediment and Erosion Control (CISEC) or equivalent training
Post-Construction RequiredYes
Turbidity StandardNo numeric NTU effluent limit in the general permit; narrative standard applies