Testing the water

County and City Zoning Overview

A zoning ordinance can restrict any of the following:

  • Height, number, and size of buildings or structures allowed in an area
  • Percentage of a lot that can be occupied
  • Size of yards, courts, or other open spaces
  • Population density
  • Location and use of buildings, structures, and land for trade, industry, residence, or other purposes
  • Use of tents, trailers, and portable or potentially portable structures for residential purposes


Board of Supervisors

The county board of supervisors has the authority to pass ordinances that regulate land use on land that is located within the county but outside of the city limits. A zoning ordinance divides the county into districts for different types of land use, such as agricultural, commercial, industrial, and residential. Supervisors can set regulations in one district that differ from regulations in another, but restrictions must be uniformly applied for each type of building within a district.

When adopting a county zoning ordinance, county supervisors must ensure that the regulations are consistent with a comprehensive plan designed to fulfill the following objectives:

  • Preserve the availability of agricultural land
  • Protect soil from wind and water erosion
  • Encourage efficient development
  • Lessen roadway congestion
  • Secure safety from fire, flood, panic, and other dangers
  • Protect the health and general welfare of county citizens
  • Provide adequate light and air
  • Prevent overcrowding
  • Avoid undue population concentration
  • Promote the conservation of energy resources
  • Promote access to solar energy
  • Facilitate adequate transportation, water, sewage, schools, parks, and other public requirements 


Agriculture Exemption

Zoning should be utilized to carefully plan non-agricultural use of property to avoid conflicts with agricultural uses. Land, buildings, or structures primarily used for agricultural purposes, including farm houses, are exempt from county zoning ordinances and city zoning ordinances that apply outside of the city limits. Iowa law allows cities to extend their zoning ordinances two miles beyond city limits with county approval. The exemption applies even if the farming operation does not provide the primary source of income for the family. The exemption does not apply to structures or buildings located on the floodplain of any river or stream. Landowners are not required to apply or obtain approval to qualify for the agricultural exemption; however, nonagricultural uses are subject to zoning even if located on a farm.


Ordinance Adoption 

Iowa law sets out the following process for adopting or amending a county zoning ordinance:

  1. The county zoning commission drafts the ordinance, holds at least one public hearing, and makes recommendations in a final report to the board of supervisors.
  2. The board of supervisors holds at least one public hearing, reviews the public comments, and votes on the ordinance.

The drafting and approval process may take anywhere from a few months to a few years depending on the time necessary to debate or gain consensus over the most appropriate land use regulations for the community. Some boards of supervisors, usually in urban areas, have appointed a separate committee to draft the comprehensive plan and zoning ordinance before the drafts are provided to the zoning commission to fulfill its statutory requirements. If a county zoning ordinance relates to any structure, building, dam, obstruction, deposit, or excavation in or on the floodplains of any river or stream, then prior approval by the Department of Natural Resources (DNR) is required to establish, amend, supplement, change, or modify the regulation or to grant any variation or exception from the regulation. 

Zoning Commission 

The board of supervisors must appoint a county zoning commission and these members must be composed of eligible electors residing outside the incorporated area. The county board of supervisors decides how many people will serve on the commission.

With permission from the supervisors, the zoning commission may form contracts with professional consultants, regional planning commissions, the Iowa Department of Economic Development, and/or the federal government to help draft the language of the ordinance.

The board of supervisors is ultimately responsible for determining the district boundaries, the zoning regulations that apply in those districts, and the adoption of the zoning ordinance. However, the board cannot act to adopt or make changes to the ordinance without receiving a final report from the zoning commission.

Once the report is received, the board of supervisors must hold at least one public hearing, with adequate public notice, to take comments on the proposed ordinance before voting on it. Following the adoption of an ordinance, copies of the plan should be sent or made available to neighboring counties, cities within the county, the regional planning commission, as well as public libraries within the county. 


Ordinance Amendments

After the ordinance is adopted, the zoning commission is responsible for making recommendations for amendments or changes to the board of supervisors as needed. The commission drafts the changes, holds public hearings on those changes, and submits their final recommendations in a final report to the board of supervisors. The supervisors must hold a public hearing and vote on the amendments before they can take effect. Amendments can be as small as changing the district for a property such as from agricultural to residential or as large as changing an entire chapter or section of an ordinance.

Landowners may protest the amendment of a county ordinance with a petition signed by the owners of 20% or more either of the area included in the proposed change or the area adjacent to and within 500 feet of, the proposed change. If there is a protest, the ordinance will not be effective until at least 60% of the board of supervisors, not just those present at the meeting, vote in favor of the change. The protest works best for smaller zoning district changes to make the supervisors aware of concerns. Otherwise, the 60% supermajority vote is essentially irrelevant as the majority needed to adopt any ordinance for both three and five-person supervisor boards is over the 60% threshold. It only becomes relevant if two county supervisors from a five-person board are absent from the decision meeting.


Zoning Administrator

A zoning administrator, who is appointed by the board of supervisors, is responsible for the enforcement of zoning ordinances. In most counties, those duties include interpreting the ordinance, granting building permits, and staffing the county zoning commission and board of adjustment. The administrator may also hold another position within the county or city governments such as the county sanitarian.


Board of Adjustment

The county supervisors must appoint a five-member board of adjustment, each appointed to five-year staggered terms. All members of the board must be composed of eligible electors residing outside the incorporated area. The board of adjustment does not change the zoning ordinance, but may: 

  • Hear and decide appeals of the zoning administrator’s decisions
  • Hear and decide on special exemptions to the zoning ordinance 
  • Grant variances from the terms of the ordinance when literal enforcement will result in unnecessary hardship, so long as it still fulfills the general purpose and intent of the ordinance


Appeal Process

Any aggrieved person affected by the administrator’s decision of enforcing the zoning ordinance may appeal the decision to the board of adjustment. Appellants should file a notice of appeal with the administrator’s office and the board of adjustment within a reasonable amount of time from the enforcement decision. To reverse a decision of the administrative officer, a majority vote by the board of adjustment members must be in favor of such a reversal. If the board of adjustment grants a variance, the board of supervisors has the authority to review and remand the board of adjustment’s decision for further review. However, if the claim is remanded, the effective date of the variance will be delayed for 30 days from the date of remand. 

Once the board of adjustment reaches a decision, the parties have 30 days in which they may appeal to the district court. It is important at this point to involve an attorney if you haven’t already done so.


Disclaimer: This document is intended for general informational purposes only and is not meant to provide legal advice for your specific situation or to infer an attorney-client relationship. Please contact your legal representative with any questions regarding your rights and available options. This document was last updated January 2024 and may not reflect the most recent changes in the law. For additional information, contact your county Farm Bureau office.