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Master Matrix

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.

The following links provide additional information about 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).

Master Matrix document

Master Matrix Technical Advisory Committee

Critical public areas

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

Map of Counties that adopted the CER in 2020
Map of Counties that adopted the CER in 2019
Map of Counties that adopted the CER in 2018
Map of Counties that adopted the CER in 2017
Map of Counties that adopted the CER in 2016
Map of Counties that adopted the CER in 2015
Map of Counties that adopted the CER in 2014

High Quality Water Resources

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.