Objectives of Ultimate Capacity

“Ultimate Capacity” is a growth management tool that attempts to provide an answer to the following question: How do communities facilitate enough high-density development to support transit without triggering concurrency restrictions on development? Snohomish County has adopted rules and regulations that essentially allow a lower level of service on roads designated as ultimate capacity.

One of the main objectives of GMA is to create more compact, viable, livable urban areas utilizing increased densities, especially within urban centers. This creates challenges for the transportation systems because increased densities create increased traffic congestion. Concurrency is the GMA tool that places a limit on the amount of congestion that communities will tolerate in certain areas before stopping further development. The long-term ‘solution’ to the traffic congestion in the most urbanized areas is good local transit service which is only ‘economically viable’ when high density residential and commercial development are in place. Thus there is a challenge. How do communities facilitate high-density development, to the point where transit becomes viable, without triggering concurrency restrictions on development? The following table shows the GMA objectives addressed by Snohomish County’s rules and regulations for ultimate capacity.

GMA Objective in RCW 36.70A.020 How the Use of Ultimate Capacity Relates to the GMA Objective
(1) Urban growth. Encourage development in urban areas where adequate public facilities and services exist or can be provided in an efficient manner. Designation of certain arterial as ultimate capacity will enable increased density of both residential and commercial development in the surrounding (and immediate) areas served by the arterial to increase the viability of more efficient modes of transportation including transit, vanpools and carpools.
(2) Reduce sprawl. Reduce the inappropriate conversion of undeveloped land into sprawling, low-density development. Snohomish County’s adopted GMA Comprehensive Plan identifies the areas suitable for higher density urban development. Without designations of ultimate capacity on arterials in these areas (once they have been improved to a certain level), concurrency restrictions can prevent the increased densities of development necessary to fully achieve these higher densities, forcing growth into lower density areas or even outside the urban growth area.
(3) Transportation. Encourage efficient multimodal transportation systems that are based on regional priorities and coordinated with county and city comprehensive plans. Efficient multi-modal systems depend upon high density residential and commercial development. Ultimate capacity is a tool to help achieve that density.
(7) Permits. Applications for both state and local government permits should be processed in a timely and fair manner to ensure predictability.
Determination of ultimate capacity streamlines concurrency determinations for developments impacting such arterials.
(12) Public facilities and services. Ensure that those public facilities and services necessary to support development shall be adequate to serve the development at the time the development is available for occupancy and use without decreasing current service levels below locally established minimum standards.
All developments impacting arterials designated as ultimate capacity would still be subject to concurrency, but the determination of ultimate capacity would effectively establish a lower level of service standard and shift the focus to multimodal transportation. Development impacting ultimate capacity facilities are required to meet new Transportation System Management (TSM) requirements (e.g. access control) and either meet revised (more intensive) Transportation Demand Management (TDM) requirements, or meet criteria for transit compatibility. Determinations of ultimate capacity also include commitments to additional road improvements, TSM actions, and/or TDM actions by the County. Examples might include access control, periodic signal coordination, signal upgrades, and support for corridor-level employer commute trip reduction programs.