Who is required to file a Construction Design Statement (CDS)?
All new or existing confinement feeding operations must file a CDS with the DNR prior to starting construction of a formed manure storage structure if after construction or expansion, the operation will have an animal unit capacity (AUC) of 501 to 999 animal units (AU). The CDS is also required as part of the construction application documents for an operation that is not required to have a PE. For these operations, producers can voluntarily use a professional engineer to design the formed storage. If a producer chooses to use a PE to design and seal a site specific design for formed storage, the producers will need to file a Professional Engineer Design Certification form with the DNR, instead of a CDS.
If a new or existing confinement feeding operations plans to construct or expand a formed manure storage structure and the operation will have 1,000 animal units or more, a professional engineer may be required. .
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Who is required to have a professional engineer (PE) licensed in Iowa design and seal their confinement feeding operation structures?
Only permitted size operations that meet or exceed the threshold engineering requirements must have a professional engineer (PE) licensed in Iowa design and seal their confinement feeding operation structures.
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What are the threshold requirements that require a professional engineering design?
Because all unformed storage must be designed and sealed by a PE, the threshold engineering requirements apply to operations that use formed storage and have been established at:
- Swine farrowing/gestating operations, with an animal unit capacity (AUC) of 1,250 AU or more
- Swine farrow-to-finish operations, with an AUC of 2,750 AU or more
- Cattle confinement operations (including dairies) with an AUC of 4,000 AU or more
- Other operations with an AUC of 3,000 AU or more
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Who is not required to file a Construction Design Statement (CDS)?
SAFOs: A CDS is not required if after construction or expansion the confinement feeding operation has an animal unit capacity (AUC) of 500 AU or less. These are small animal feeding operations or SAFOs. However, a SAFO must still comply with other state requirements before starting construction.
Permitted operations above threshold requirements: A CDS is not required if the confinement feeding operation meets or exceeds threshold requirements or if it uses an anaerobic lagoon, aerobic structure, earthen basin or egg washwater structure. However, designs must be signed and sealed by a professional engineer (See above).
Voluntary use of a professional engineer: A CDS is not required if you decide to use an engineer. In this case, in lieu of submitting a CDS you may submit engineering documents, including a statement approved by a professional engineer (PE) certifying that the formed manure storage structure will be constructed according to the minimum standards of Iowa Code chapter 459, Subchapter III, and 567 Iowa Administrative Code (IAC) chapter 65.
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Who qualifies as a professional engineer?
For construction or expansion of confinement feeding operations in Iowa, a PE is a professional engineer licensed in the state of Iowa or an engineer working for the USDA-Natural Resources Conservation Service (NRCS).
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CAUTION: This web page summarizes Iowa laws, including the DNR's administrative rules. While every effort is made to keep this page current and accurate, there are frequent changes to the laws governing animal feeding operations; the law will prevail in the event of a conflict between this web page and the law . We encourage users to consult Iowa Code Chapter 459 and 567 Iowa Administrative Code chapter 65 for current statutory provisions and administrative rules.
