1.3 Other Policy Standards and Guidelines

Last Updated: 8-19-2019Print page

The design of Seattle’s street right-of-way has a significant impact on the livability of the city as well as the health, safety, and welfare of its residents. The width of a sidewalk, radius of a corner, number of lanes on the roadway, and the location of utilities, such as overhead power lines and underground waterlines all play a role in shaping neighborhoods. A street is part of the public realm and all streets provide some form of open space including view corridors and green space in between private property and the curb.

Streets Illustrated contains mandatory design standards that must be followed when designing and constructing improvements to the public right-of-way. Design standards present a consistent approach to designing each element of the right-of-way to best serve the traveling public, support land use patterns, and encourage economic growth in the City and the region. When reviewing and approving projects in Seattle’s right-of-way, the City of Seattle makes every attempt to balance the vision for a project with adopted policy, regulation, user acceptance, and public safety.

The design standards in Streets Illustrated are to be used in conjunction with other applicable City, State, and National standards for right-of-way design. More information on these standards can be found in City of Seattle Standard Plans and Specifications and Washington State Minimum Design Standards.

Streets Illustrated also contains design guidance, which the City recommends be considered when designing right-of-way improvements. Compliance with design guidance is encouraged but not required.

Citywide Policy Guidance for Right-of-Way Improvements

The design standards in Streets Illustrated have been developed consistent with appropriate local, state, and national guidelines for right-of-way design. The standards also support citywide policy defined in companion documents to Streets Illustrated, including the City of Seattle Comprehensive Plan, Seattle 2035, the Move Seattle 10-year Strategic Plan, the City modal plans (Bicycle, Transit, Pedestrian & Freight), the SDOT Complete Streets ordinance (2007), and the Stormwater Code (2016).

Seattle’s Complete Streets Guiding Principle

Seattle’s Complete Streets guiding principle is to design, operate, and maintain Seattle’s streets to promote safer and convenient access and travel for all users — pedestrians, bicyclists, transit riders, for people of all abilities, as well as for freight, and motor vehicle drivers.

City of Seattle Comprehensive Plan

The City of Seattle Comprehensive Plan, 2035, is a 20-year policy plan that defines the vision of how Seattle will grow in ways that sustain its residents’ values. The Comprehensive Plan and its transportation policies were updated in 2016. The City first adopted a Comprehensive Plan in 1994 in response to the state Growth Management Act of 1990. Seattle 2035 makes basic policy choices and provides a flexible framework for adapting to real conditions over time. It is a collection of the goals and policies the City will use to guide future decisions about how much growth Seattle should take and where it should be located. Seattle 2035 also describes in a general way how the City will address the effects of housing and employment growth on transportation and the movement of goods, especially in designated urban centers and villages.

The Transportation Element of Seattle 2035 encourages people to use alternative transportation options. One way to do that is through the urban village strategy’s goal of concentrating most new housing, jobs, and services near one another in small areas, so that more trips can be made by walking, biking, or transit. Another way is to support new public transit options. The Transportation Element contains policies that set the stage for street design standards that will match future street improvements to the types of uses and neighborhoods the street is serving. One of the goals (TG 2) is to “Allocate space on Seattle’s streets to safely and efficiently connect and move people and goods to their destinations while creating inviting spaces within the rights-of-way.” The policies related to this goal support this document, Streets Illustrated (the Right-of-Way Improvements Manual).

City of Seattle Stormwater Code

The Seattle Stormwater Code are regulations to protect people, property, and the environment from damage caused by stormwater runoff. Seattle complies with the Municipal Stormwater Discharge National Pollutant Discharge Elimination System (NPDES) Permit, issued by the Washington State Department of Ecology. The Stormwater Code addresses drainage, where the stormwater from your site needs to go, on-site stormwater management and why it’s important, erosion control requirements during construction and grading, flow control and stormwater treatment requirements, and how the Code is enforced. The Stormwater Code is Title 22, Subtitle VIII of the Seattle Municipal Code and informs the design standards in Streets Illustrated.

City of Seattle Standard Plans and Specifications

The City of Seattle has developed design and construction standards for improvements in public right-of-way to protect the health, safety, and welfare of the public and to minimize post-construction maintenance and repair costs. These standards shall be followed, together with the design standards presented in Streets Illustrated and as required by the Seattle Municipal Code (SMC).

City of Seattle Standards for the design and construction of specific elements of right-of-way improvements are contained in two publications that are referred to in Streets Illustrated by the shortened combined title, Standard Plans and Specifications.

City of Seattle Standard Plans for Municipal Construction. Individual plans from this publication are referred to in Streets Illustrated as “Standard Plan” followed by the number of the plan.

City of Seattle Standard Specifications for Road, Bridge, and Municipal Construction. Individual specifications from this publication are referred to in Streets Illustrated as “Standard Specification” followed by the number of the specification.

Washington State Minimum Design Standards

In addition to the design criteria in this chapter and Seattle’s Standard Plans and Specifications, right-of-way design elements must also comply with the minimum design standards for major arterial and secondary arterial streets in the State of Washington. These minimum design standards are established and adopted in the Revised Code of Washington (RCW) 35.78 Streets – Classification and Design Standards, and have been published in the City and County Design Standards.

Exceptions from Washington State Minimum Standards

Per the City and County Design Standards, it is noted that the professional engineer in charge of the project must evaluate each design situation.

“In adopting these standards, the (State’s design review) committee seek to encourage standardization of road design elements where necessary for consistency and to assure that motoring, bicycling, and pedestrian public safety needs are met. Considerations include safety, convenience, context sensitive solutions, proper drainage, and economical maintenance. The committees recognize that cities and counties must have the flexibility to carry out the general duty to provide streets, roads, and highways for the diverse and changing needs of the traveling public.”

These standards cannot provide for all situations. They are intended to assist, but not to substitute for, competent work by design professionals. It is expected that land surveyors, engineers, and architects will bring to each project the best skills from their respective disciplines. These standards are also not intended to limit any innovative or creative effort, which could result in better quality, better cost savings, or both. An agency may adopt higher standards to fit local conditions. Special funding programs may also have varying standards.”

– excerpted from the City and County Design Standards

In any case, evaluation and ultimate approval of deviations to existing street design standards are the responsibility of SDOT.

Streets Illustrated is one of many resources for a project applicant proposing to do work in the street right-of-way. Information in Streets Illustrated is:

While Streets Illustrated strives to be inclusive, it is the responsibility of the project to insure compliance with all city, state, and federal requirements such as the Americans with Disabilities Act (ADA) and the Manual on Uniform Traffic Control Devices (MUTCD).