ARC 0212D

ARC 0212D

TRANSPORTATION DEPARTMENT[761]

Adopted and Filed

Rulemaking related to traffic signal synchronization

    The Transportation Department hereby rescinds Chapter 143, “Traffic Signal Synchronization,” and adopts a new Chapter 143, “Traffic Signal Coordination,” Iowa Administrative Code.

Legal Authority for Rulemaking

    This rulemaking is adopted under the authority provided in Iowa Code section 364.24.

State or Federal Law Implemented

    This rulemaking implements, in whole or in part, Iowa Code section 364.24.

Purpose and Summary

      This chapter lays out requirements regarding the installation and coordination of traffic signals.

Public Comment and Changes to Rulemaking

    Notice of Intended Action for this rulemaking was published in the Iowa Administrative Bulletin on January 7, 2026, as ARC 9875C. Public hearings were held on the following date:

     ?   January 28, 2026

    No one attended the public hearings. No public comments were received. No changes from the Notice have been made.

Adoption of Rulemaking

    This rulemaking was adopted by the Department on March 10, 2026.

Fiscal Impact

     This rulemaking has no fiscal impact to the State of Iowa. Local public agencies bear the costs of installing and maintaining traffic signal coordination equipment and services.

Jobs Impact

    The rulemaking maintains an already established requirement that certain traffic signal installations within a city be operated in a coordinated manner.

Waivers

    Any person who believes that the application of the discretionary provisions of this rulemaking would result in hardship or injustice to that person may petition the Department for a waiver of the discretionary provisions, if any, pursuant to 761—Chapter 11.

Review by Administrative Rules Review Committee

    The Administrative Rules Review Committee, a bipartisan legislative committee which oversees rulemaking by executive branch agencies, may, on its own motion or on written request by any individual or group, review this rulemaking at its regular monthly meeting or at a special meeting. The Committee’s meetings are open to the public, and interested persons may be heard as provided in Iowa Code section 17A.8(6).

Effective Date

    This rulemaking will become effective on May 20, 2026.

    The following rulemaking action is adopted:

    ITEM 1.  Rescind 761—Chapter 143 and adopt the following new chapter in lieu thereof:

CHAPTER 143

TRAFFIC SIGNAL COORDINATION

761—143.1(364) Definitions.

    “Arterial street” means any U.S. or state numbered route, controlled access highway, or other major street or highway designated by the city within its respective jurisdiction as a part of a major arterial system of streets or highways.

    “Coordination” means the establishment of a timing relationship between adjacent traffic signals.

    “Traffic signal” means any permanently installed, electrically powered traffic control device by which traffic is alternately directed to stop and to proceed.

    “Traffic signal system” means two or more traffic signals operating in a coordinated manner.

761—143.2(364) Applicability. This chapter applies to all cities with more than three traffic signals within the corporate limits.

761—143.3(364) Conditions.

    143.3(1) Unless a traffic engineering study documents that it is not practical, traffic signals within one-half mile of each other along an arterial street or in a network of intersecting arterial streets shall be operated as a traffic signal system.

    143.3(2) Traffic signal timing and operational plans are to be developed by the application of traffic engineering principles to provide maximum traffic flow efficiencies and safety for all users.

    143.3(3) All traffic signal installations and operations are to comply with the department’s traffic control device manual.

761—143.4(364) Contact information. Information regarding this chapter is available from: Traffic and Safety Bureau, Iowa Department of Transportation, 800 Lincoln Way, Ames, Iowa 50010. Additional information and guidance may be found at www.iowadot.gov/consultants-contractors/traffic-safety/document-resource-library/traffic-safety-manual.

These rules are intended to implement Iowa Code section 364.24.

[Filed 3/18/26, effective 5/20/26]

[Published 4/15/26]

EDITOR’S NOTE: For replacement pages for IAC, see IAC Supplement 4/15/26.