Making Connections: Alley Improvements

Some things to know about alleys:

Property owners are responsible for alleys next to their property. (Alleys are defined as any unopened street areas next to their property.)

Unimproved alleys (those not improved to City standards) are not considered part of the City's street system and are not maintained by the City.

Alleys improved to City standards are considered part of the City's street system and are maintained by the City. However, alley maintenance funds are scarce. Currently, if the alley is damaged to the extent that there is a safety or mobility problem, the City will make a spot repair. More extensive repairs are likely to be conducted by the abutting property owners.

Improving an alley may require more than simple paving. Drainage facilities are likely to be needed, and detention (holding stormwater then slowly releasing it) may also be required to ensure that the alley improvement does not contribute to flooding basements or landsliding. City standards take this into consideration by consulting the Stormwater, Grading and Drainage Control Code. If the alley is located in an environmentally critical area, the City's Critical Areas Code may also require additional care in design and construction.

The Department of Planning and Development administers these codes and can help you understand them if you visit their Application Services Desk on the 20th floor of the Key Tower, 700 5th Avenue. They can tell you if your alley is located in an environmentally critical area also. (DPD publishes a Client Assistance Memo #501 that explains the Stormwater, Grading and Drainage Control Code. Printed copies are available at the Applicant Services Desk, or online at the DPD web site.

Garbage trucks sometimes use unimproved alleys to provide garbage and recycling pick up services as a convenience to the property owners. They are not required to do so, as unimproved alleys are not part of the City street system.


Many parts of Seattle have improved alleys. Why is the alley down the block paved and mine is not?

Development codes at the time of subdivision construction (when the buildings were first built) required installation of alley and/or sidewalk improvements and the cost was part of the original construction cost of the buildings. Property owners paid for the improvements when they bought the property.

If I want to improve my alley, where do I start?

If you are a property owner and the alley abuts your property, speak to your neighbors to see if they also wish to improve the alley.

Improvement Options:

SDOT Can Maintain the Alley at the Property Owner's Expense

You may wish to have the Seattle Department of Transportation (SDOT) undertake alley maintenance projects on your unimproved alley, but in order for SDOT to do that the alley has meet certain criteria concerning grade, slope and maneuvering room. If SDOT determines that it can work in the alley, then SDOT can apply dust palliative, undertake limited regrading, and spread and roll crushed ledge rock and other road materials to improve the driving surface. THESE MAINTENANCE ACTIVITIES ARE USUALLY UNDERTAKEN AT THE ADJACENT PROPERTY OWNER'S EXPENSE. SDOT does not have a maintenance budget for working in alleys. To schedule an appointment to discuss alley maintenance, please call Charles Bookman at (206) 233-0044.


Doing the Improvement Yourself (or with your neighbors privately)

You may wish to have your alley improved, but not wish to spend as much money as would be required to meet City standards. Contact a private contractor and ask for an estimate of improvements to City standard and an estimate that meets your needs that may be a less intensive improvement than City standard. If the alley were improved at less than City standard, the City would not be responsible for any maintenance of the alley. You will be required to have a Street Use Permit from the City to conduct a private alley improvement project. Please visit the Street Use Permit Counter, 37th Floor Key Tower, 700 5th Avenue between 8:30am and 5:30pm for more information or call 684-5283.

You may wish to have your alley improved, but not wish to pave it fully as required by City standards. Contact a private contractor and ask for an estimate that meets your design ideas. (For instance, you may wish to leave a grass strip down the middle and along the sides of the alley to reduce the amount of impermeable surfacing. If this is your desire, be sure to check subsurface conditions to see that additional water will infiltrate through the soil and will not add to potential basement flooding or landslide hazard. A geotechnical engineer can be helpful in making these analyses.) You will need a street use permit to construct a private alley improvement.