Manure Storage Structures
There are two main types of manure storage structures for confinement feeding operations: formed and unformed. A manure storage structure does not include egg washwater storage structures.
Formed structures usually have concrete or steel walls and sides. By definition, a formed manure storage structure means a covered or uncovered impoundment used to store manure from an animal feeding operation, which has walls and a floor constructed of concrete, concrete block, wood, steel, or similar materials. Similar materials may include, but are not limited to, plastic, rubber, fiberglass, or other synthetic materials. Materials used in a formed manure storage structure shall have the structural integrity to withstand expected internal and external load pressures.
Left: A formed manure storage structure made of steel. Middle: A concrete formed manure storage structure overflowed after the producer accidentally left a hose running. State law requires producers to keep the liquid manure level at least one foot below the top of a formed structure. Right: A common type of manure storage used in Iowa for swine operations is the below-building pit. The manure is removed and land applied as a fertilizer for crops. Photo courtesy of ISU Extension.
Unformed manure storage structures include several types of impoundments, built of soil or earth. These earthen storage basins were very popular in Iowa until the mid-1990s, when concerns about their usage prompted legislative changes that encouraged formed storage. By definition, an unformed manure storage structure means a covered or uncovered impoundment used to store manure, other than a formed manure storage structure, which includes an anaerobic lagoon, aerobic structure or earthen manure storage basin.
Left: Manure agitation and removal from an unformed manure storage structure.
Right: Lagoon used for storage of liquid swine manure is an unformed manure storage structure.
Manure Management Plans for Confinements
What is an MMP?
A manure management plan (MMP) is a tool for producers to use when they plan their nutrient placement to optimize crop production. Filling out an MMP helps producers identify the amount of manure being produced, the nutrient concentration in the manure, the number of acres that are required for land application and the amount that will be applied to each available acre. Mid-size and large producers are required by state law to fill out and submit an MMP to the DNR. MMPs can be based on the nitrogen uptake needs of the crop, although phosphorus index-based plans were gradually phased in. After 2008, all plans must be phosphorus index-based.
Who Needs a Plan?
Iowa law requires that a manure management plan (MMP) be submitted to the DNR for confinement feeding operations (totally roofed) meeting any of the following criteria:
- The operation has an animal unit capacity of more than 500 animal units and the operation was constructed or expanded after May 31, 1985;
- The operation proposes to construct a manure storage structure and will have an animal unit capacity of more than 500 animal units; or,
- A person applies manure from a confinement feeding operation located outside of Iowa on land in Iowa (does not apply if the operation's capacity is 500 animal units or less).
Manure management plans are not required for open feedlots, except when specifically required as part of a permit or an agreement with the DNR. Owners of a combination open feedlot and confinement operation must file a manure management plan (MMP) for the confinement operation if the confinement facilities have capacity for more than 500 animal units. The combined operation may also need a nutrient management plan (NMP). See combined operations for more information.
Annual Submittals for Existing Sites:
Livestock and poultry producers who must have a manure management plan (MMP) have been required to submit an annual update of the plan since 2002. If you have an MMP on file, you should submit the annual update of your MMP to the county board(s) of supervisors or designated representative (where the facility is located and to counties where manure will be spread) and to the DNR with any changes from the current plan.
The plans are due on the first of the month on a staggered deadline throughout the year and must be on DNR forms. Producers keep the same due date every year. However, as of June 30, 2009, the DNR no longer mails reminder letters before the date that the plan is due. Instead, producers can check the AFO database to see when their plan is due.
All annual submittals (see MMP Short form 542-8162) should be sent to the appropriate DNR field office. Producers are required by state law to pay an annual compliance fee when the annual updates are submitted (see Fee form 542-8064. If you are expanding or modifying your operation, you will need to submit an original MMP.
Updated MMP Submittals with the P Index:
Every fourth year, producers are required to submit a complete MMP (form 542-4000) which includes the P-Index based on updated soil tests. The complete form should be submitted following the instructions under Original MMP Submittals (see below). Check the AFO database for due dates for P-index plan updates.
Original MMP Submittals:
An original or first-time submittal of an MMP is required for the following facilities that need to have an MMP:
- new sites,
- existing sites (including poultry) that need a manure management plan (MMP) but have not previously submitted one,
- sites that have a change of ownership, or
- sites that have an existing MMP that is not on DNR forms.
If this MMP is a first-time submittal for the site, a copy must be provided to the DNR, to the county board of supervisors or designated representative where the facility is located and to any counties where manure will be spread.
If a construction permit is not needed: State law also requires producers to pay a $250 filing fee for the first-time (original) submittal of an MMP and an indemnity fee of $0.10 per animal unit, if the facility was constructed or expanded after May 31, 1995 (see Indemnity Fee form 542-4021.
If applying for a construction permit: Applicants for a construction permit, including those for sites with a change in ownership, should use the forms in the Construction Permit Application (542-1428). Send the MMP to the DNR Spencer field office at Iowa DNR, Animal Feeding Operations Permitting, 1900 N. Grand, Gateway North, Suite E17, Spencer, IA 51301. For questions about permits, contact Paul Petitti at 712-262-4177. All other MMPs should be sent to the appropriate DNR field office, listed on the form.
Dry Manure Sales under 200 or 200A: Confinement feeding operations that sell manure under Chapter 200 or 200A (licensed under the Iowa Department of Agriculture and Land Stewardship) may submit an abbreviated MMP (form 542-8069) to the DNR along with a copy of the IDALS license. An updated copy of the IDALS license must be submitted with annual updates. The MMP form and IDALS license must also be submitted to the board of supervisors (or designated representative) in the county where the facility is located and to counties where manure will be applied. See Fees listed below for information on the annual compliance fee, the filing fee and the indemnity fee.
Annual Compliance and Other Fees
Annual compliance: An annual compliance fee of $0.15 per animal unit is required whenever the updated annual manure management plan (MMP) is submitted. The annual fee is required for those operations that already have an MMP and are not expanding or modifying a structure. Fees can be paid and submitted with the DNR form 542-8064 or 542-8064.
Original MMP: A $250 filing fee is required when an original (first time) MMP is filed (whether the site must have a construction permit or not). Original MMPs are required for first time submittals and when a site is expanding, modifying, or changing ownership of a structure. Producers who submit an original MMP should pay only the $250 filing fee and the indemnity fee, using form 542-4021 or 542-4021 if a permit is not required.
Operations that need to apply for a construction permit to build a new confinement, or expand or modify an existing facility are required to pay a $250 construction permit application fee in addition to the fees above. Fees can be submitted with form 542-1428.
Indemnity fees: A manure storage indemnity fee (one-time fee) must be paid when constructing or expanding an operation or when changing ownership of the operation. The fee is $0.10 per animal unit if a construction permit is not required. It is $0.10 per animal unit when changing ownership if not expanding or modifying the manner or volume of in which manure is stored. However, if applying for a construction permit, this fee varies according to the animal species and size of the operation. (see Form 542-1428 or 542-1428).
County Verification and Responsibilities
The producer or the applicant for a construction permit is required to send a manure management plan (MMP) to the board of supervisors in the county where a facility is located and in the counties where manure is applied. The board or a designated representative of the board must verify that the MMP has been received. For unpermitted and existing permitted sites, receipt of the MMP ends the county's obligation. Producers must have the county sign a verification form, DNR form 542-8046 or 542-8046 and return it to the DNR.
For MMPs that are received with an application for a construction permit, the county is required to provide public notice that a permitted confinement feeding operation is proposed. The county may elect to hold a public hearing and to provide comments to the DNR. Producers must have the county sign the DNR verification form 542-1428 and return it to the DNR. In counties that have adopted the master matrix, the county has the obligation to review the construction permit application using the master matrix and make a recommendation to approve or disapprove the application to the DNR. For more information, see the Master Matrix and Construction Permits.
Phosphorus Index-based Plans
Senate File 2293 phased in phosphorus index-based manure management plans (MMPs) through August 2008, with the longest implementation dates given to those who already had an MMP on file with the DNR. The schedule below indicates when producers needed to submit phosphorus index-based plans
Implementation Date for P Index-based plans
|Original MMP Submitted
||P Index-based MMP due
|Prior to April 1, 2002
||First annual update after Aug. 25, 2008
|Between April 1, 2002 and Oct. 24, 2004
||First annual update after Aug. 25, 2006
|On or after Oct. 25, 2004
For more information on P index-based plans.
Confinement feeding operations must continue to comply with other manure application requirements, including separation distances and applying manure without polluting state waters. For more information, see the section on manure applicator certification.
Producers are required by state law to keep records for five years of manure application and make them available to DNR for review. There are some record keeping requirements for commercial manure applicators as well. For more information, see land application of manure. The DNR provides a recordkeeping form which producers can use, form 542-8002 or 542-8002.
Requirements for Manure Management Plan (MMP) Forms
To be acceptable, the manure management plans (MMPs) must meet specific criteria outlined in Iowa law and DNR rules, including basing maximum applications on the nitrogen and phosphorus needs of the crops being grown, identifying the specific land areas on which manure will be applied, and specifying planned application methods and timing. The original plans are filed with the DNR and the appropriate county(ies), and a current plan must be maintained within a 30-mile radius of the operation and made available for review by DNR staff.
Read the Instructions and Introduction for information about who must submit an MMP, who must submit annual updates, what parts of the form must be filled out and what parts are optional, new fee requirements, calculating animal units and where to submit your plan or plan update. Or, the MMP fact sheet also has additional information.
Producers filing plans with DNR should use one of the DNR forms listed below:
- The MMP form 542-4000 is available as a document, spreadsheet or a pdf. It includes both nitrogen-based and phosphorus index-based plans.
- The short version of the form 542-8162 or 542-8162 can be used for annual updates.
- An abbreviated MMP form 542-8069 or 542-8069 can be used for sales of dry manure under Chapter 200 or 200A.
- Additional information and reference tables can be found in Appendix A.