TRN-1.28 - Curb Extensions for Buildings and Planning Actions

I. Purpose

This administrative rule establishes the conditions under which the Portland Bureau of Transportation (PBOT) will require curb extensions as an element of corner reconstruction for building permits and land use actions. Curb extensions decrease the overall width of the roadway and can serve as visual cues to drivers that they are entering an area of increased pedestrian activity. They also increase the overall visibility of pedestrians by aligning them with the edge of the parking lane and reducing the crossing, improving the safety of an intersection. Curb extensions can be used to enforce compliance with ORS 811.550 which prohibits parking within 20 feet of a crosswalk at an intersection. Curb extensions are identified in the City's Transportation System Plan (TSP) as an effective safety and traffic calming measure and are recognized in the City's Pedestrian Design Guide as a preferred element.

All street design classifications referenced in this rule are designated by the Portland Transportation System Plan.

II. Applicability

Curb extensions may be required when corner reconstruction is required as a condition of a building permit or land use review, as described in Administrative Rule TRN-1.30.

This rule applies only to corners at unsignalized intersections where there is a  curbside on-street parking lane. The requirements and exemptions shown on the Curb Extension Policy Map (Appendix A) supersede previously adopted streetscape or district plans that identify locations for curb extensions. When an existing corner is ADA-compliant, reconstruction of the corner solely to provide a curb extension is not required unless it fulfills a condition of approval for land use review. 

III. Requirement

1. In the Central City and Northwest Plan Districts, curb extensions are required at unsignalized intersections. The curb extension must extend into both intersecting streets (see Figure 1), except at exempt or infeasible locations as described in section IV below.
2. Outside of the Central City and Northwest Plan Districts, single curb extensions are required on any street with a Pedestrian Classification of City Walkway or Major City Walkway that has a traffic classification greater than Local Service, except as described in section IV below. The curb extension must extend into this street.

View full size image of two intersection streets with curb extension

IV. Exemptions and Feasibility

The Curb Extension Policy Map (see Appendix A) shows the streets where curb extensions are required as a condition of a development action if frontage improvements are required by TRN-1.30.Curb extensions will not be required where they are infeasible or impractical due to the modal priorities or existing or future design of the street.

The Curb Extension Policy Map also shows locations that are exempt from the requirement. Exempt locations are:

1. In a freight district.
2. On a City or Major City Bikeway that is less than 42 feet wide, curb to curb, unless the street design classification is Civic Main Street or Neighborhood Main Street, or
3. Where there is a planned transit or bicycle improvement at the curb and a curb extension would preclude the planned improvement.

Feasibility will be determined by the City Engineer. Locations where the curb extension requirement will be assessed for feasibility include:

1. Where an underground water or sewer utility is within six feet of the existing curb line and would therefore be underneath the new curb extension, as determined from City GIS, survey, or during the Public Works permitting process.
2. Where utility infrastructure such as maintenance holes, fire hydrants, utility poles, and inlets may make a curb extension impractical or infeasible. This determination will be made during the Public Works engineering and design process.

Additionally, PBOT will decline requests from a permittee to build concrete curb extensions at locations that are excluded from the requirement, as identified on the Curb Extension Policy Map in Appendix A. The applicant may request a design exception, which will be reviewed by the City Traffic Engineer.

V. Curb Extension Design

1. Obstructions such as catenary poles, street lighting, building appurtenances, stormwater facilities, utility vaults, or building projections are not permitted to be placed in curb extensions on corridors with a bicycle or transit designation other than Local Service in the Transportation System Plan.
2. Refer to the PBOT Traffic Design Manual for general guidelines that apply to curb extensions. Additionally, Chapter 6 of the 2025 Stormwater Management Manual provides guidance for designing stormwater facilities in curb extensions.

VI. Background

While curb extensions are an important tool for enhancing pedestrian visibility and comfort at crossings, they can preclude or complicate future bike and transit improvements. With the adoption of the Climate
Action Plan and 2035 Comprehensive Plan, PBOT has increased its focus on implementing protected bicycle lanes and enhanced transit corridors, including bus queue jumps. Both these facility types often depend on using the curb zone. Implementation of these facilities can sometimes be made more difficult and/or more expensive by the presence of curb extensions in the curb zone, or altogether infeasible. In some cases, curb extensions may need to be removed to accommodate bicycle and/or transit uses adjacent to the curb.

Policy 9.6 of the City's Comprehensive Plan prioritizes walking, bicycling and transit—in that order--over other modes of transportation. That policy also states that "All users' needs are balanced with the intent of optimizing the right of way for multiple modes on the same street" and that a "Policy-based rationale is provided if modes lower in the ordered list are prioritized." This administrative rule recognizes that pedestrian safety and crossing improvements can be provided in a manner that also allows for needed bicycle and transit improvements.

Near-term transit and bike improvements referenced in section IV.C include:

• Planned bikeways on the TSP one- to ten-year list
• Funded bikeways
• Enhanced Transit Corridors projects on the one- to ten-year project list
• Central City in Motion projects (all are in a one- to ten-year timeframe)
• Projects in the Quick Build Programs for Bike Network Completion and Transit Spot Improvements

VI. Reference

Pursuant to Rule Making Authority of City Code Title & Chapter 3.12.

VIII. Effective Date

This administrative rule is effective two weeks after adoption.