Stormwater Permit Information

Stormwater Permit Requirements

The NPDES stormwater program regulates some stormwater discharges from three potential sources:

1. Construction activity that disturbs one or more acres or which is part of a larger project that disturbs one or more acres in total.
2. Certain types of industrial or commercial activities.
3. Many city storm sewer systems in larger communities or those near larger communities. 

Stormwater general permit applications (NOIs) may be submitted online at the Stormwater General Permit Database.

No Exposure Exemption

If all industrial materials and activities at your facility are protected by a storm resistant shelter that prevents exposure to rain, snow, snowmelt, and/or runoff, you may not need a stormwater permit. Industrial materials or activities include, but are not limited to, material handling equipment or activities (including storage, loading and unloading, transportation, or material conveyance; industrial machinery; raw materials; intermediate products; by-products; final products; or waste products.

To qualify for a no exposure exemption, complete and submit the No Exposure Certification Form. A No-Exposure Certification must be provided for each qualifying facility.

The no exposure exemption is ONLY available on a facility-wide basis; it is not for individual outfalls. If any industrial activities or materials at your facility are exposed to precipitation, the facility is not eligible for the exemption.

Stormwater NPDES Permit Options

There are two options available when applying for an NPDES permit for a stormwater discharge associated with industrial activity:

1. Applying for coverage under a general stormwater permit.
2. Applying for an individual permit.

More information on these options is available below.

General Stormwater NPDES Permits

A stormwater discharger may apply for coverage under a general permit by submitting a Notice of Intent (NOI) for coverage. General NPDES permits contain terms and conditions for a certain class of facilities. General permits are not specific to any one discharger; rather, the general permit identifies which dischargers may be eligible for coverage under the permit.

The Iowa DNR has adopted three general permits for stormwater, as follows:

• General Permit #1 - Stormwater Discharge Associated With Industrial Activity (Excludes Construction)
• General Permit #2 - Stormwater Associated With Industrial Activity For Construction Activities (Land Disturbing 1 Acre Or More)
• General Permit #3 - Stormwater Discharge Associated With Industrial Activity From Asphalt Plants, Concrete Batch Plants, Rock Crushing Plants, And Construction Sand And Gravel Facilities

Additional forms and permit guidance is available on the Stormwater Permits, Guidance & Forms webpage.

The stormwater general permits are applicable to discharges composed of only stormwater. Mixtures of stormwater and non-stormwater where the non-stormwater would require an individual NPDES permit are not covered by Iowa's stormwater general permits (refer to the general permits for additional details). 

Any discharge with a federal effluent limit is required to be permitted by an individual NPDES permit. Any discharge from a facility or construction site that may temporarily degrade an Outstanding National Resource Water or an Outstanding State Resource Water is also required to be permitted by an individual NPDES permit, as stipulated in 567 Chapter 64 of the Iowa Administrative Code and in the Iowa Antidegradation Implementation Procedure. General permit coverage is not available for these discharges. 

General Permit NOI Submittal:

Stormwater dischargers applying for coverage under a general permit must complete and submit a Notice of Intended Action (NOI). A complete NOI includes an online or paper form, proof of public notification, and the general permit fee.

To submit an NOI online, use the Stormwater General Permit Database. Paper NOI forms and guidance are also available on the Stormwater Permits, Guidance & Forms webpage.

For coverage under a stormwater general permit, a complete NOI must be submitted and an authorization approved and issued by the DNR prior to the start of operations or soil disturbing activities.

General Permit Fees:

All stormwater general permit applications (NOIs) must be accompanied by the following fees:

Individual NPDES Permits

An individual NPDES permit is only applicable to one discharger and is issued for a specific discharge. Only one individual permit will be issued to a facility. If a discharger has an existing individual NPDES permit, that permit will be modified to include its stormwater outfalls. 

Individual Permit Application Forms:

Stormwater dischargers applying for an individual permit must complete NPDES Industrial Application Form 1, Form 2F, and Form 5. Additional forms may be required if the stormwater is mixed with non-process wastewater (Form 2); process wastewater from existing sources (Form 3); or process wastewater from new sources (Form 4). These individual permit application forms are available on the NPDES Permit Application Forms webpage.

For an individual NPDES permit, an application must be submitted 180 days prior to the start of operation.

Individual Permit Fees:

The five year permit fee for an individual stormwater NPDES permit is $1250.00.