Confinement feeding operations that plan to build, modify or expand must meet state requirements for the new construction. It is important to determine as early as possible, at least 120 days before you plan to begin construction, what size the proposed operation will be and the type of manure storage that will be used. Once size and type of storage are known, you can determine which state requirements must be met.
Left: Determine the finished confinement's size and type of manure storage at least 120 days before construction is scheduled to begin. Those two factors will determine which state regulations apply to a proposed operation.
Determining size of operation: To determine the size of your proposed operation, calculate the animal unit capacity or AUC. Caution: If you have ownership or management in another operation that is or will be located within one-half mile of the proposed site; or that would be sharing a common area or system for manure disposal, irregardless of the distance, the two operations may be considered one operation and the animal unit capacities of both must be added together to determine the size of the operation. Please contact the DNR field office engineer in Spencer at 712-262-4177 for assistance in determining if two adjacent operations are considered as one.
Determining storage type: There are two basic types of storage, formed and unformed. Formed manure storage structures usually have concrete or steel walls and floors, and must be strong enough to withstand internal and external load pressures. Unformed manure storage structures or earthen basins include anaerobic lagoons, earthen aerobic structures and earthen manure storage basins. If a combination of formed and unformed storage will be used, the requirements for the unformed storage apply.
Right: Formed manure storage structures built of concrete must meet concrete standards that went into effect on March 24, 2004.
Types of confinement feeding operations: Based on size and storage type, there are three basic categories of confinement feeding operations:
1. Permitted - A construction permit is required prior to building, modifying or expanding all sizes of operations that use unformed storage. A construction permit is also required prior to building, modifying or expanding an operation that uses formed storage if the final animal unit capacity will be 1,000 animal units or more. See pre-construction requirements and design standards.
2. Non-permitted - Formed Manure Storage - A construction permit is not required for building, modifying or expanding a confinement feeding operation with a proposed animal unit capacity from 501 to 999 animal units that uses formed storage. However, pre-construction requirements and design standards must be met before construction begins. See pre-construction requirements.
3. Small - Formed Manure Storage - Neither a construction permit or a manure management plan are required for small operations, 500 or less animal units, that use formed manure storage, but some pre-construction requirements apply. See pre-construction requirements.
Producers can use a summary (*.pdf file) of requirements for all three types of confinement feeding operations to determine what they need to submit.
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.