SW

Stormwater Directory

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

IA(3 more)

Rows with an amber indicator differ across selected states.

Field
IA
Iowa
NPDES ProgramState-Delegated
Permitting AgencyIowa Department of Natural Resources (IDNR)
Permit NameNPDES General Permit No. 2 — Stormwater Discharge Associated with Industrial Activity from Construction Activities (Permit IAR100000)
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 to IDNR at least 2 business days before commencement of land-disturbing activities; authorization is automatic upon submittal if the NOI is complete
Application MethodOnline via Iowa DNR's EQ (Electronic Reporting and Permitting) portal at https://programs.iowadnr.gov/npdespermits/; paper NOI also accepted
Permit FeeNo permit application fee for NPDES General Permit No. 2 (construction stormwater); fees may apply for individual NPDES permits
SWPPP RequiredYes
PE Certification RequiredNo
SWPPP Template AvailableYes
Inspection FrequencyAt least every 7 days and within 24 hours after any storm event producing ≥ 0.5 inches of rainfall in a 24-hour period; inspection frequency may be reduced to every 14 days during periods of frozen ground and no construction activity
Inspector QualificationInspector must be a qualified person who is knowledgeable in the principles and practice of erosion and sediment controls and familiar with the SWPPP; Iowa does not require a specific state-issued inspector certification for construction stormwater
Post-Construction RequiredYes
Turbidity StandardNo numeric NTU effluent limit in General Permit No. 2; narrative standard applies