construction photo
Construction Requirements

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.

Iowa’s open feedlots are places where animals are kept in unroofed or partially roofed areas. To be considered an open feedlot, animals are fed and maintained in pens for at least 45 days in a one-year period. Unlike animals on pasture, manure from the animals is concentrated and the ground is bare of vegetation.


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 1250/2500 feet 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 your local DNR field office for assistance in determining if two adjacent operations are considered as one.

There are two basic types of storage, formed and unformed. Formed manure storage structures are usually concrete floors with concrete or steel walls, 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.

Formed manure storage structures built of concrete must meet the Iowa Administrative Code concrete standards that went into effect on March 24, 2004. 567 IAC 65.15(14).

First you need to determine if you own or manage another confinement operation that is located within 2,500 feet; or that utilizes a common system for manure storage regardless of how far they are apart. If the answer is "yes," you must first contact your nearest DNR Field Office, before proceeding with separation distance determination.

All sites, no matter how many animals, need to meet the minimum separation distances.

Distances that Apply to all Confinement Feeding Operations, regardless of animal unit capacity:

  • Surface intakes of an agricultural drainage well or water source other than major (Excluding farm ponds, privately owned lakes or when a secondary containment barrier is provided) 500 feet
  • Wellhead or cistern of an agricultural drainage well or known sinkhole or major water source (Excluding farm ponds, privately owned lakes or when a secondary containment barrier is provided) 1,000 feet
  • Designated wetlands (2,500 feet)
  • Right-of-way of a thoroughfare maintained by the state or a political subdivision (100 feet)
  • 200 feet from a water source required for a dry-bedded confinement feeding operation structure.

You need to check the separation distances to a residence, business, church, school, public use area, water wells, major water sources, sinkholes, water sources, designated wetlands, environmentally sensitive areas and public thoroughfares.


Form # Rev Date
542-1420 Minimum Separation Distances for Construction or Expansion of Confinement Feeding Operation Structures 2/2019


Concrete Construction

For tips on proper concrete construction, check out our concrete training presentation [PDF] .


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 operations that use unformed storage regardless of size. 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 greater than 500 but less than 1,000 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 nor a manure management plan are required for small operations (SAFO), 500 or less animal units, that use formed manure storage, but separation distance requirements apply. See pre-construction requirements.

Open Lot Feeding Operations

Minimum Requirements: Open feedlot producers are required to manage manure, process wastewater, settleable solids and effluent from the feedlot accordingly.


Pre-Construction Requirements for:

Pre-construction requirements for permitted projects, all confinement feeding operations that use unformed manure storage or operations with 1,000 animal units or more that use formed manure storage. A construction permit and manure management plan are required for new construction, modifications and expansions. Owners must apply for a construction permit at least 60 days prior to start of construction, and should plan for additional time (e.g. 18 to 120 days) to allow for mail delivery or appeal actions by the county. For permitting requirements, see the following items that are possibly needed to complete your application package:

Pre-construction requirements for non-permitted confinement feeding operations, proposed sites with an animal unit capacity greater than 500 but less than 1,000 animal units and that use formed manure storage. 

A construction permit is not required, however, a Construction Design Statement (CDS) and a manure management plan, form 542-4000, must be submitted at least 30 days prior to the start of construction, even if a manure management plan has been filed before. Some construction requirements and design standards must be met. For specific requirements, see the following items that are possibly needed to receive your construction approval letter:

Pre-construction requirements for small animal feeding operation, or SAFO, confinement feeding operations with an animal unit capacity of 500 animal units or less and that use formed manure storage.

While construction permits and manure management plans are not required, the following pre-construction requirements apply:

  • Distance Requirements for Construction, form 542-1420, includes small animal feeding operations (SAFOs), see definition below.  
  • Designated Wetlands
  • Storm Water Plan
  • An alluvial soils determination must be done prior to the start of any construction. Refer to the DNR's AFO Siting Atlas.
  • An artificial ground water lowering system (drain tile) must be installed if a SAFO uses formed storage that is constructed below or partially below the ground. The only time a lowering system would not be required is if a professional engineer determines that the formed storage would be constructed above the seasonal high water table according to 567 IAC 65.15(7).  

For more information, check Proper Siting Requirements or contact your local DNR field office.

Open feedlots, solids settling facilities, feed storage runoff control structures and AT systems shall be separated from water wells as follows: for both public and private wells, 200 feet from shallow wells and 100 feet from deep wells.

Settled open feedlot effluent basins shall be separated from water wells as follows:

  • Public wells. 1,000 feet from shallow wells and 400 feet from deep wells;
  • Private wells. 400 feet from both shallow and deep wells.

 

These requirements apply to open feedlots that are required to have a National Pollutant Discharge Elimination System or NPDES permit.

combined

Contact your local DNR field office with any questions.

Livestock producers who have animals in both confinement (totally roofed) and open feedlot (partially roofed or unroofed) facilities face a somewhat more complex situation than producers who have only one type of housing. They may need a National Pollutant Discharge Elimination System (NPDES) permit required by federal regulations if a discharge would be expected from the facility. A non-discharging open feedlot that is part of a combined operation will need to follow state regulations for open feedlots. The confinement portion of the operation will need to follow state regulations when operating or building a confinement facility. These combined facility situations can be confusing and complex, so producers are encouraged to contact their local DNR field office to ensure the correct requirements are being followed.

The following form provides additional information for livestock producers who need a permit for a combined operation.


combined lot

A New Animal Truck Wash Facility that plans on constructing a truck wash that will wash all single-unit trucks, truck-tractors, semi-trailers or trailers washed at the facility that are owned by multiple people or owned by the same person but planning on using more than an average of 2,000 gallons per day must submit a Truck wash construction permit application packet, form 542-0982. The application packet must contain the designs of the truck wash and a Nutrient Management plan (NMP), NMP form 542-2021.

An animal truck wash facility must obtain a construction permit prior to any of the following:

  1. Constructing or expanding an animal truck wash effluent structure.
  2. The department has previously issued the animal truck wash facility a construction permit and the volume of the animal truck wash effluent would be more than the volume approved by the department in the previous construction permit.
  3. The animal truck wash facility is part of a confinement feeding operation and all of the following apply:
    • The department has issued a construction permit or an NPDES permit for the confinement feeding operation or a letter approving a construction design statement for the confinement feeding operation in lieu of a construction permit.
    • The animal truck wash effluent will be added to an existing manure storage structure resulting in a total stored volume greater than that approved in the construction permit or the construction design statement approval letter.
  4. The animal truck wash facility is part of an open feedlot operation and all of the following apply:
    • The department has issued a construction permit or an NPDES permit for an open feedlot operation.
    • The animal truck wash effluent will be added to an existing settled open feedlot effluent basin resulting in a total stored volume greater than that approved in the construction permit or NPDES permit.
  5. An animal truck wash facility is constructed or expanded as part of a small animal feeding operation that includes a manure storage structure, the animal truck wash effluent will be added to the manure storage structure.
    • The department has issued a construction permit or an NPDES permit for an open feedlot operation.
    • The animal truck wash effluent will be added to an existing settled open feedlot effluent basin resulting in a total stored volume greater than that approved in the construction permit or NPDES permit.
  6. An animal truck wash facility is constructed or expanded as part of a small animal feeding operation that includes a manure storage structure, the animal truck wash effluent will be added to the manure storage structure.

     

Contact your local DNR field office with any questions.



For new construction, choosing a good site may be one of the most important decisions a producer can make. The DNR's AFO Siting Atlas may help producers choose the optimum site for a proposed facility. If building a deep pit barn, find construction tips and requirements in Concrete Training.

Proper Siting of an Animal Feeding Operation using karst terrain and alluvial soils maps
The DNR has developed the AFO Siting Atlas to help livestock and poultry producers who are planning a new animal feeding operation, or the expansion or modification of an existing operation. This application gives a quick overview of the landscape features that must be considered when planning construction. The application can be especially helpful in determining the locations of alluvial soils, karst topography and sinkholes.

Alluvial soils and karst describe areas in Iowa that may be vulnerable to flooding or groundwater contamination. Alluvial soils formed from materials deposited by running water, thus a site located in alluvial soils may be in a floodplain. Karst terrain refers to areas where soluble bedrock lies close to the ground surface. Karst areas are often characterized by sinkholes and losing streams. Water and contaminants in these areas can travel quickly through underground passageways to wells, springs, and streams.

Iowa laws have specific requirements for building, expanding or modifying open feedlots and confinement feeding operations located in the 100-year floodplain. Knowing if a potential site has alluvial soils is one step in determining if the site could be in a floodplain and if building restrictions could apply. Depending upon specific site conditions, construction may be prohibited or a floodplain permit may be required.

All animal feeding operation structures have a "high damage potential," meaning flood protection (both structural integrity and elevation of the lowest opening) must be provided to the level of the 100-year floodplain plus one foot. In addition, the construction must allow for the conveyance of flood flows.

Iowa law prohibits placing confinement feeding operations within 1,000 feet of a sinkhole, and sets specific separation distances from other protected waters. Also, animal producers who plan to build, modify or expand a confinement feeding operation structure will need to find out if the proposed location is in karst terrain.

AFO Siting Atlas
Use the AFO Siting Atlas as one tool to evaluate potential sites for environmental concerns.

The AFO Siting Atlas was created because of requests from the livestock industry. It’s designed to help producers evaluate potential locations for livestock and poultry sites. Producers, consultants and DNR staff can quickly locate a potential site and determine if a new or expanding facility is likely to be located on alluvial soils or in karst terrain.

Use the instructions below for the AFO Siting Atlas. Go to the AFO Siting Atlas.

  1. Click on the upper arrow to zoom in to the location you are interested in, or type the address or legal description of the proposed location into the appropriate search tool at the bottom left of the application.
  2. Click on the proposed site location on the map to estimate AFO site parameters. Look for specific distances in the pop-up box on the right.
  3. Determine whether the site is in “alluvial soils” or "within 1,000 feet of a mapped sinkhole" or in "potential karst," using the pop-up box.
  4. Color overlays can be turned on or off in the Map Layers list.
  5. You will need to print out the map for documentation. To print an image of your site, go to File – Print in your web browser.

Map interpretation and documentation
Since it was impossible to analyze the soil and subsurface properties of every piece of land in Iowa, the DNR GIS Section created maps that contain all of the potential karst and alluvial areas in the state. Producers who wish to locate a site in these areas will have to consult with an engineer, soil scientist or qualified staff from the USDA Natural Resources Conservation Service to confirm the mapping or submit documentation to refute the alluvial or karst mapping. Additional information about this process can be found in a fact sheet on alluvial and karst determinations.

Alluvial soils. If the footprint of the proposed confinement or manure storage structure is within "Alluvial Soils" (area shaded blue), please use the new PERMT online application system, for a floodplain determination.

Karst terrain. If the footprint of the proposed confinement or manure storage structure is within "Karst" or "Potential Karst" (areas shaded dark pink), a karst report will need to be completed, if you have questions please contact a DNR animal feeding operations permitting engineer at 712-262-4177 or 712-262-4177.

Producers/Consultants: To document the determination, please attach a printed copy of the map, with the footprint of the proposed structure marked clearly, to the appropriate materials:

  • Permitted confinements - Submit with construction permit application and send to DNR Field Office in Spencer.
  • Non-permitted confinement sites - Submit with MMP and send to the appropriate DNR Field Office.
  • SAFOs (small animal feeding operations) do not need to submit documentation, but should keep a copy with their plans.

If you receive correspondence from the DNR Flood Plain Section, please include a copy of that correspondence with your submitted materials.

Alluvial soils are soils deposited by running water and are often located in existing floodplains. The AFO Siting Atlas is used to determine if a potential animal feeding operation site would be located on alluvial soils, and, thus, possibly in a floodplain.

Floodplain Requirements for Confinement Feeding Operations
State law requires anyone wishing to build, modify or expand a confinement or manure storage structure located on alluvial soils to determine if the proposed site will be located in a 100-year floodplain. State law prohibits construction of a confinement in the 100-year floodplain of a major watersource. Use the AFO siting Atlas to check if your proposed site is on alluvial soils. You will need to know the township, range and section of the proposed location. Please document your findings from the map and submit that document with your construction design plans. Small animal feeding operations - please keep a copy of the documentation on-site, unless a construction permit is needed.

  • Confinements with less than 1,000 animal unit capacity using formed structures:
    If the proposed location of a confinement with less than 1,000 animal units is located on alluvial soils, the producer must petition the DNR for a declaratory order to determine if the site is in a 100-year floodplain. The petition must follow the format outlined in the 561 Iowa Administrative Code (IAC), 6.7. The DNR has developed a form for producers' convenience, Petition for a Declaratory Order, form 542-8157. This form may be filled out and submitted via the new PERMT online application system.
  • Confinements needing a construction permit:
    If the proposed site of a confinement with 1,000 animal units or more is located on alluvial soils, the construction permit applicant must request a floodplain determination from the DNR. The determination is different than the petition for a declaratory order. For a floodplain determination, please use the new PERMT online application system.
Floodplain Requirements for Open Feedlots:
While open feedlots are not prohibited from constructing in alluvial soils, they must meet certain DNR requirements. For proposed open feedlot structures, a floodplain construction permit must be obtained if the stream drainage area is greater than 10 square miles. Producers can use the AFO Siting Atlas to determine if a proposed site is in alluvial soils. The PERMT online application system can be used to determine if a floodplain permit is required and used to apply if one is required. For questions about this process, contact the DNR Flood Plain section at floodplain-help@dnr.iowa.gov or call 866-849-0321.

Karst terrain is characterized by the presence of easily dissolved bedrock (limestone and dolomite) near the ground surface. Because carbonate rocks can be dissolved by groundwater, karst areas are often characterized by sinkholes, springs, and losing streams where some surface flow is lost to groundwater. Groundwaters and surface waters in these areas are highly vulnerable to contamination because contaminants can travel quickly from the surface through open fractures and caves to aquifers, springs, and streams and are not likely to be filtered by soils.

Producers can check the AFO Siting Atlas to determine if a potential animal feeding operation site would be located near a sinkhole or in karst terrain.

Karst Requirements for Confinement Feeding Operations
The Iowa Administrative Code prohibits new, expanding and modified confinement operations from constructing unformed manure storage (earthen basins) in karst terrain.

The Iowa Administrative Code also prohibits new, expanding and modified confinement operations from constructing within 1,000 feet of a sinkhole unless secondary containment is provided. Any new confinements in karst terrain, with more than 500 animal units, must meet upgraded concrete standards, by providing the DNR with soil borings indicating the depth to bedrock below the proposed formed structures. If there is less than five feet to bedrock below the bottom of a proposed formed structure, the construction plans must be signed and sealed by a professional engineer, and a two-foot clay liner must be installed below the structure. Water monitoring for ammonia-nitrogen may also be required for new confinements in karst terrain.

The master matrix is a scoring system that can be used to evaluate the siting of permitted confinement feeding operations. Counties that have adopted a construction evaluation resolution can use the master matrix. Counties must re-adopt the construction evaluation resolution annually between January 1 and January 31, starting in 2004, to continue to use the master matrix. Producers in counties that have adopted the matrix must meet higher standards than other permitted facilities. Before they can be approved for construction, they must earn points on the master matrix for choosing sites and using practices that reduce adverse impacts on the environment and the community. Producers must have 50% (440 points minimum) of the total score and at least 25% of the available points in each of the three subcategories of air, water and community impacts to pass the master matrix.

Who Needs the Master Matrix?
The Master Matrix must be completed by operations applying for a construction permit, unless they can meet one of the following two exemptions:

  • The county, where the operation is located or will be located, has not adopted the construction evaluation resolution or does not have a valid construction evaluation resolution when the application is submitted; OR
  • The operation was first constructed prior to April 1, 2002 and is expanding to an animal unit capacity (AUC) of 1,666 AU or less. This exemption applies in all counties.

Note: producers must also submit the supporting master matrix documents (e.g. design, operation and maintenance plans as written in certain matrix items).

High Quality Water Resources

Critical public areas

County officials and staff can find more information about adopting a construction evaluation resolution on the Iowa State Association of Counties' website. (off-site) Look under News, and then under Topics of Interest.

The following maps show which counties adopted the Construction Evaluation Resolution (CER) to use the Master Matrix:

2002 Master Matrix Technical Advisory Committee

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.