Clearances are the minimum distances between elements in, under and above the street right-of-way. Clearance requirements are a key factor in how space within the right-of-way and on private property adjacent to the right-of-way can be used. Maintaining appropriate clear distances between certain elements in the right-of-way and on private property is necessary for a variety of reasons. Safety is a key consideration—for the traveling public, the property owner and for operations and maintenance crews who must access elements in the right-of-way for routine maintenance or repair. Appropriate clearances also enable the proper growth and development of trees and landscaping, and help protect and maintain both overhead and underground utilities.

Lateral Clearances

Vertical Clearances

Trees : For more information about clearances and trees, including conditions for deviating from the standard clearance listed below due to site constraints; refer to Section 4.14.2 Clearances from Street Trees. Factors to consider for a deviation from the standard required clearances between street trees and utilities may include the depth and age of the pipeline, the possible use of root barriers, the nature of the plantings, fire code requirements, and other factors.

Clearances from Trees

Railroad clearances: Certain requirements apply if a project is in the on, over, under, or in the vicinity of land or facilities owned and/or operated by railroad operators. There are three reference points for determining clearances: 1) the franchise agreement for a particular piece of railroad in the right-of-way; 2) state requirements; and 3) federal requirements. Whether state or federal (or both) requirements apply depends on the track classification and function.

Clearances from Railroad Facilities

Other clearances pertaining to railroads shall conform to Clearance Rules and Regulations Governing Common Carrier Railroads prescribed by the Washington Utilities and Transportation Commission. Minimum clear distance above a railroad track shall be 23 feet.

If your project is on or adjacent to property owned by railroad operators, contact the operator for information about required clearances or additional permit requirements.

Bicycle parking clearances: In addition to the clearances defined in the table below, bicycle parking facilities must not encroach upon a minimum of 6 feet of clear sidewalk space. Narrow racks such as the inverted-U rack, must have a total minimum combined clearance of 6’ around the rack, measured from any point on the rack.

Standard Clearances from Bicycle Parking

Electrical utility clearance requirements: Applicants who are developing a new project must pay attention to the potential conflicts between existing electrical facilities in the public right-of-way and their new building during project planning, design, demolition and construction. The following criteria applies:

Minimum horizontal and vertical clearances between overhead power distribution and buildings or other structures: The Seattle City Light (SCL) Overhead Power Distribution requires a minimum horizontal and vertical clearance from buildings and structures. The purpose of this clearance is to keep the general public and workers without high voltage electrical expertise out of harms way.

Clearances also provide adequate space for qualified electrical workers to operate safely and efficiently during construction and long term operations and maintenance activities. Additional clearances are required to allow for regular building maintenance such as window washing activities.

Zero lot line developments: Zero lot line developments often encounter clearance problems with high voltage overhead and underground electrical facilities and wires. Land use setback requirements alone, for example when minimal front yard setbacks are allowed, are likely not adequate to account for required clearances from overhead electric utilities. Note that clearances are also required where electrical facilities are located in alleys. Thus proposed buildings may need to be located further back from property lines to accomplish required clearances.

Permit applicants must adhere to electric utility clearance requirements. Please contact Seattle City Light to arrange a meeting as early as possible in your design process. We recognize that each proposed development location, adjacent utilities, streetscape, and development request is unique. Even if poles and wires are not immediately adjacent to your property at this time, it is best to assume clearances are needed until you meet with Seattle City Light and verify otherwise. Additional and relocated infrastructure will be needed to serve the demand for growth.

Refer to Figure 4-23: Seattle City Light Utility Clearance.
Refer to Electrical Utility Clearances Notes.

The applicant is advised to document the existing site conditions early in the design phase to identify any elements that may have a required clearance to help avoid possible costly site modifications during permitting.