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Road Services - Transportation Concurrency Management Program

Transportation Concurrency Expert Review Panel

The Transportation Concurrency Expert Review Panel (TCERP) meets on July 21, from 2 to 4 p.m. in room 3-F on the 3rd floor of the King Street Center, 201 S. Jackson St, Seattle. The meeting is open to the public. The agenda (.pdf) involves discussion of transportation concurrency options and strategies for unincorporated King County.  Read the July 21 meeting minutes. (.pdf)

Proposed 2013 Transportation Concurrency Update

About transportation concurrency

"Concurrency" was first required after Washington State passed the 1990 Growth Management Act or "GMA".externalink Concurrency as defined in state law means transportation facilities must be able to accommodate trips created by new development for the development to occur, “…local jurisdictions must adopt and enforce ordinances which prohibit development approval if the development causes the level of service on a locally owned transportation facility to decline below the standards adopted in the transportation element of the comprehensive plan…" (RCW 36.70A.070(6)(b)).

King County first implemented the Transportation Concurrency Management (TCM) Program by adopting its first Comprehensive Plan following the GMA in 1994, with TCM becoming effective in 1995. The program has undergone many changes since 1995 culminating with the most recent TCM changes being adopted by the King County Council on Oct. 6, 2008, as part of the 2008 King County Comprehensive Plan Update. The new TCM program changes became effective on Oct. 30, 2008. The transportation concurrency policies are found in Chapter 7, Transportation.

The King County TCM program was significantly changed in 2008. Key elements of the program are summarized as follows:

  • Actual travel time is collected by corridor segments on County principal and minor arterials and certain State highways
  • Concurrency testing is by large geographic “Travel Sheds” where travel patterns share common characteristics
  • Concurrency testing evaluates travel time by roadway mileage within each travel shed
  • Rural mobility areas are identified, which are defined by land use, enhance multimodal travel, and reduce length of vehicle trips in rural areas
  • 85% of travel shed arterial mileage must meet concurrency standards for the travel shed to pass the concurrency test
  • Residential and nonresidential proposals are tested by the same concurrency map
  • Concurrency is based on pass or fail of travel shed status as shown on the concurrency map; no certificate of transportation concurrency is issued
  • Clear identification is made of failing corridor routes that are the primary reason a travel shed is out of compliance
  • Increased transparency is created for projects needed to bring a travel shed back into compliance

2012 Adopted Concurrency Management Program

The 2012 Annual Update has been adopted by the King County Council. The update consists of the following maps:

In addition to the maps, a background report was sent to the County Council. The Annual Report, Transportation Concurrency Management Program, 2012 Annual Update, provides information on data collection and testing in 2012.

Adopted concurrency regulations and level-of-service standards can be found in Title 14.70 of the King County Code. Allow up to three months after the most recent update is adopted by the King County Council for the King County Clerk’s Office to add (codify) the new ordinance changes to the King County Code.

Check your property's concurrency status

Check your property's transportation concurrency status using the King County Parcel Viewer. Input your property's address or 10-digit parcel identifier. After the application shows your property information, select "Districts Report" located on the lower left-hand side of the page. On the "Districts Report" refer to the row titled "Transportation Concurrency Management" for your "Pass" or "Fail" determination. Technicians at the Department of Permitting and Environmental Review (DPER) handling your application will check this on your pre-application form.

If your property fails concurrency

Should your property be identified as failing concurrency, check with a DPER staff member to see if your property or development proposal qualifies under the category “Minor Developments and Public and Educational Facilities,” which may allow you to proceed with your application (see King County Code 14.70.285). If the proposal does not meet these criteria, you cannot proceed with your development proposal until the property is identified as passing concurrency. You should check each year around October to see if the annual update of transportation concurrency has changed the status of your property.

Concurrency annual update

The Transportation Concurrency Management Program will collect travel time data on the county arterials in the spring of each year and test each travel shed for concurrency. The results are scheduled to be adopted each year in the fall or winter by the King County Council in the form of an updated Transportation Concurrency Map. Travel sheds passing today may fail the next concurrency update depending on the data collected. If a project development application is not complete, as defined by DPER as of the effective date of the new map, then concurrency passed today will not pass during the year the newly adopted map is in effect if the travel shed fails. The proposed development will not be allowed to proceed. Property owners and potential developers need to be aware of this possibility and allow enough time to complete their application before the concurrency update goes into effect.

The Annual Update is planned to be transmitted to the King County Council in the fall of each year. Once transmitted, the proposed ordinance transmittal package will be reviewed by the council Transportation Economy and Environment Committee. A recommendation of the committee will be sent to the full council for public hearing and adoption. Once the ordinance is adopted by the council, the updated Transportation Concurrency Map will become effective 10 days after the King County Executive signs the ordinance.

Contact us

For further information, please contact:

Planning Unit
King County Road Services Division
201 South Jackson Street
M/S KSC-TR-0317
Seattle WA 98104-3856

Information from the Road Services Division's website is available to people with disabilities in alternate formats upon request by calling 206-477-3839 or 711 for the TTY relay service.

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