II. RELATIONSHIP OF PLANNED LAND USE TO TRANSPORTATION
A. Land Use Map and Travel Demand
Snohomish County is divided into urban, rural and resource lands as designated by the Future Land Use Map (FLUM). These broad categories of land use are mutually exclusive. Table 3 provides the approximate area and acreage for the categories as well as distinctions between urban and rural uses. (ref. 11) It is important to note that much of western Snohomish County is urban and will continue to urbanize.
Land Use Category |
Area (Sq. Miles) |
Acreage (Acres) |
---|---|---|
Tribal Trust Land |
20.9 |
13,400 |
Urban Lands |
||
• County Unincorporated |
53.7 |
34,408 |
• City Incorporated |
151.2 |
96,786 |
Rural Lands |
365.5 |
233,954 |
Resource Lands (varied) |
495.9 |
317,369 |
National Forest |
1,027.6 |
657,671 |
Water/Undefined |
82.4 |
52,735 |
Total Land Area |
2,197.2 |
1,406,323 |
Source: PDS, 2013.
1. Land Use Forecasts
Travel demand is directly related to the type and intensity of the land uses that make up the community and region. Snohomish County and city governments are responsible for planning under the GMA to accommodate a fair share of the region’s expected growth and development. The county and cities must designate adequate amounts of land for residential and commercial land uses within their comprehensive plans and provide appropriate zoning and special use classifications that guide and regulate development.
Growth and demand for land development emanates from increases in population and employment in the region and county itself. The county receives a forecasted range of population growth that must be planned for from OFM. In a collaborative process, the county and cities establish targets for urban and rural growth in the form of population, employment, and housing growth targets. Table 4 presents the population, employment, and housing growth targets upon which the land use element of the county’s comprehensive plan is based. Information is presented by UGAs and for the total remaining rural area.
Growth Area |
2011 |
2035 |
% Change |
---|---|---|---|
Population |
|||
Arlington UGA |
18,489 |
26,002 |
41% |
Darrington UGA |
1,420 |
2,161 |
52% |
Gold Bar UGA |
2,909 |
3,319 |
14% |
Granite Falls UGA |
3,517 |
8,517 |
142% |
Index UGA |
180 |
220 |
22% |
Lake Stevens UGA |
33,218 |
46,380 |
40% |
Maltby UGA |
NA |
NA |
NA |
Marysville UGA |
60,869 |
87,798 |
44% |
Monroe UGA |
18,806 |
24,754 |
32% |
Snohomish UGA |
10,559 |
14,494 |
37% |
Stanwood UGA |
6,353 |
11,085 |
74% |
Sultan UGA |
4,969 |
8,369 |
68% |
SW County UGA |
434,425 |
582,035 |
34% |
Rural Areas |
121,287 |
140,125 |
16% |
Total |
717,000 |
955,257 |
33% |
Growth Area |
2011 |
2035 |
% Change |
---|---|---|---|
Employment |
|||
Arlington UGA |
8,660 |
20,884 |
141% |
Darrington UGA |
500 |
886 |
77% |
Gold Bar UGA |
223 |
666 |
199% |
Granite Falls UGA |
760 |
2,276 |
199% |
Index UGA |
20 |
25 |
25% |
Lake Stevens UGA |
4,003 |
7,821 |
95% |
Maltby UGA |
3,190 |
6,374 |
100% |
Marysville UGA |
12,316 |
28,113 |
128% |
Monroe UGA |
7,779 |
11,781 |
51% |
Snohomish UGA |
4,871 |
6,941 |
42% |
Stanwood UGA |
3,456 |
5,723 |
66% |
Sultan UGA |
866 |
2,081 |
140% |
SW County UGA |
187,653 |
279,479 |
49% |
Rural Areas |
14,693 |
23,323 |
59% |
Total |
248,990 |
396,373 |
59% |
Growth Area |
2011 |
2035 |
% Change |
---|---|---|---|
Housing Units |
|||
Arlington UGA |
7,128 |
10,018 |
41% |
Darrington UGA |
682 |
948 |
39% |
Gold Bar UGA |
1,205 |
1,304 |
8% |
Granite Falls UGA |
1,412 |
3,516 |
149% |
Index UGA |
117 |
127 |
9% |
Lake Stevens UGA |
12,281 |
17,311 |
41% |
Maltby UGA |
71 |
71 |
0% |
Marysville UGA |
22,709 |
32,936 |
45% |
Monroe UGA |
5,838 |
7,443 |
27% |
Snohomish UGA |
4,545 |
6,115 |
35% |
Stanwood UGA |
2,634 |
4,577 |
74% |
Sultan UGA |
1,887 |
2,972 |
57% |
SW County UGA |
178,958 |
243,179 |
36% |
Rural Areas |
48,973 |
55,816 |
14% |
Total |
288,440 |
386,333 |
34% |
Source: Amended Ordinance NO. 14-129
Population can be expected to increase from 717,000 in 2011 to 955,257 by 2035. This amounts to a 33 percent increase in population. Also, employment as part of the expanding regional economy can be expected to increase from 248,990 in 2011 to 396,373 by 2035. This amounts to an increase of approximately 59 percent in employment. Housing units can be expected to increase from 288,440 in 2011 to 386,333 in 2035, a 34 percent increase.
2. Travel Characteristics
Increases in population, employment and associated land development in turn cause increases in travel demand, congestion and the need for arterial and transit-related improvements. Numerical measures of travel demand have been computed based on the county’s land use policies and the resulting growth forecasts. The transportation measures are summarized in Table 5 Snohomish County Summary of Travel Statistics. These statistics indicate a substantial increase in travel demand towards the year 2035 that will likely cause additional delay and congestion on the transportation system.
Category |
Magnitude |
---|---|
Daily Vehicle Trips |
|
2012 |
1,976,000 |
2035 |
3,071,000 |
% Increase |
55% |
Daily Vehicle Miles of Travel |
|
2012 |
18,710,000 |
2035 |
23,360,000 |
% Increase |
25% |
Daily Rideshare Vehicle Trips (1) |
|
2012 |
546,000 |
2035 |
758,000 |
% Increase |
39% |
Daily Transit Boardings (2) |
|
2012 |
48,000 |
2035 |
67,000 |
% Increase |
40% |
A.M. Peak Hour Vehicles |
|
2012 |
119,000 |
2035 |
168,000 |
% Increase |
41% |
P.M. Peak Hour Vehicles |
|
2012 |
172,000 |
2035 |
235,000 |
% Increase |
36% |
(1)Includes two-person carpools.
(2)Represents a linked-trip that does not reflect transfer-related boardings.
Source: Snohomish County Public Works 2014.
3. Planned Land Use and Transportation Services
Different transportation modes can be applied to effectively serve different types and intensities of land use within unincorporated Snohomish County. It is appropriate, and the policy of the county, to vary the plans for transportation modes and infrastructure to reflect the location, type and intensity of particular land uses. Designated land uses in unincorporated county as presented by the county’s comprehensive plan can be grouped in three broad categories. These categories are: a) urban centers; b) urban areas outside centers; and c) rural areas and resource lands.
a. Centers
Focusing a large part of urban growth within compact centers has long been the county’s preferred approach to growth management for the unincorporated county. This preference reflects a commitment to the goals of the GMA. The county subsequently has committed considerable time and resources to defining criteria for designating centers, allocating growth and planning infrastructure to serve centers.
Centers can be developed in various forms to adapt to the unincorporated county’s growth and transportation needs. Centers are designed to have defined boundaries within which higher residential and employment densities occur. The design of a center encourages transit use, pedestrian activity, and bicycle connections. Fixed-route transit service and appropriate roadway access should be provided to serve centers. In most cases, centers are connected by transit emphasis corridors which are served by or planned to be served by bus rapid transit (BRT), light rail, or other high-capacity transit (HCT). There are four centers designations on the Future Land Use Map (FLUM).
• Manufacturing and Industrial Centers.An area characterized by large tracts of land which are reserved for intensive manufacturing and other non-office uses. Goods access and terminal locations need to be provided for truck, rail, or waterway. Appropriate road access and transit service is necessary to provide for employee commutes.
• Urban Centers.An area located along existing or planned high capacity transit routes and principal arterials where the highest residential and employment densities can be accommodated. These are pedestrian and transit oriented areas with a mix of high-density residential, office and retail uses, and community facilities.
• Urban Villages.A pedestrian oriented, neighborhood scale, mixed-use area with retail and office uses, public and community facilities, and high-density residential developments. In some cases Urban Villages are served by high capacity transit, but for the most part transit service is provided by core and local transit routes.
• Transit/Pedestrian Villages.An area within designated Urban Centers that surrounds an existing or planned high capacity transit station. Transit Pedestrian Villages feature uses that enhance and support the high capacity transit station. Emphasis shall be placed on a compact walkable area that is integrated with multiple modes of transportation.
b. Urban Areas Outside Centers
Urban growth areas (UGAs) are characterized by a defined geographic boundary within which urban growth is planned to occur and where urban infrastructure such as sewers is to be provided. A variety of land uses and concentrations of growth will occur within these UGAs. The land use element of the comprehensive plan allows for an average net residential density of at least four to six dwelling units per acre while taking into account environmental constraints. Higher density, mixed-use development is also planned to occur throughout the UGAs. The majority of population and employment growth is expected to take place within these urban areas. This, of course, would result in higher densities in the future than have occurred historically within these geographic areas.
Transportation services provided within the urban areas would consist of fixed-route transit service, roadway access, park-and-ride lots, bicycle facilities, and walkways. Fixed-route transit service will connect urban centers, circulate within the urban areas, and connect urban areas together. This transit service would consist of BRT on major transit corridors operating every 15 minutes or better, corridor service on other transit emphasis corridors operating between 15 and 20 minutes, and local service operating at frequencies between 20 minutes and one hour. Arterial roadways will continue to be the major transportation service provided within urban areas.
Arterial roadway expansion is planned to occur within urban areas and the majority of the additional transportation facilities are also located within the urban areas. Access to express bus service and other HCT system components is expected to be through park-and-ride lots, local fixed-route service to transit centers, and along transit emphasis corridors. Some park-and-ride lot capacity would be located within the urban areas to provide connections to express bus service or the regional HCT system.
Urban areas are expected to be served by bicycle and pedestrian facilities, constructed in conjunction with development, as part of roadway improvement projects where applicable, or as stand-alone projects as funding is available. The bicycle system presented within this transportation element is designed to provide both an alternative to other modes of travel and a recreational opportunity. Individuals choosing to use bicycling as a transportation mode should be able to do so within the urban areas.
c. Rural Areas and Resource Lands
Rural areas and resource lands are lands outside the designated urban growth boundaries. These two land use categories include most of the county’s forestry, agricultural, and mineral lands, as well as low density residential uses. Employment areas are planned to support the needs of rural uses, such as employment relating to resource lands and residential uses. Densities for rural areas are planned to be one dwelling unit per five acres.
Auto travel will continue to be the primary mode of transportation within rural areas and connecting rural areas to urban areas. Public transportation service to and from rural areas is likely to be demand-responsive type service or as part of a fixed-route connection between urban areas. A few roadways will be widened to provide additional capacity within the rural areas and some new rural roadways are planned by the county. Some potential exists to eliminate long dead-end local roads through development review. Transportation improvements within the rural areas will consist mainly of safety projects and minor widening projects such as turn pockets and shoulder improvements. Shoulders will also be used for pedestrian access and as bicycle facilities in addition to the planned trails system within the rural area.
B. Planning Level Transportation Analysis for County Arterials and State Highways
Level-of-service (LOS) analysis provides the basic measure by which to make judgments on transportation performance, capital improvement programming and concurrency. The methodology used in this plan to determine the potential need for capital improvements relies on a planning-level analysis in which the peak-hour volume (V) for a section of roadway is compared to the section’s maximum service volume (MSV). In the analysis, the MSV functions as the roadway’s estimated capacity, thus providing a volume-to-capacity evaluation. Existing and forecasted 2035 traffic volumes for the a.m. and p.m. system peak-hours are compared to MSV, resulting in V/MSV ratios. When the V/MSV ratio indicates there may be a potential LOS deficiency, then potential arterial improvement projects or other strategies are considered to address the potential deficiency. If a potential project that increases capacity on an arterial roadway has been identified and included in the plan, then the future MSV reflects the increased capacity.
This planning-level analysis allows the identification of arterials that potentially are operating or could eventually operate below the county’s adopted LOS standard. However, it is important to note that actual LOS determinations are made under the county’s concurrency management system (CMS), as discussed in Chapter III. During the planning-level analysis, potential arterial improvements or other strategies for addressing potential LOS deficiencies are also identified. The actual need for an improvement project to maintain LOS standards can be confirmed by detailed operational analysis under the CMS before improvement programming proceeds.
Three different agencies have responsibility for promulgating LOS standards for arterials and highways in unincorporated Snohomish County. The LOS standard for locally owned arterials is adopted by Snohomish County, the standard for regionally significant state highways (non-HSS) is adopted by the PSRC, and the standard for state highways of statewide significance (HSS) is adopted by the WSDOT. Table 6 presents a summary of the LOS standards adopted by Snohomish County, PSRC and WSDOT. While somewhat diverse in application, all the standards and methodologies are consistent with the most current version of the Highway Capacity Manual, published by the Transportation Research Board (TRB). (ref. 12)
1. County-owned Arterials
The planning-level LOS evaluation for Snohomish County relies on MSV for each LOS grade. MSVs serve as a reasonable and accurate “planning method” for estimating levels of congestion on arterials and crafting effective solutions. As noted above, this planning-level analysis allows the identification of arterials that are potentially below or could eventually be below the county’s adopted LOS standard. The County’s adopted LOS standard and concurrency management system is discussed in detail in Chapter III.
Urban Area |
Rural Area |
|
---|---|---|
County-Owned Arterials (2) |
“E” |
“C” |
Regionally Significant State Highways (non-HSS) |
||
Inner Urban Area |
“E” Mitigated (3) |
“C” |
Outer Urban Area |
“D” |
|
Highways of Statewide Significance (HSS) |
“D” |
“C” |
Source: WSDOT, 2010.
(1)Based on methodologies consistent with the most current edition of the Highway Capacity Manual.
(2)See Chapter III for a more detailed description of Snohomish County LOS standard
(3)Congestion should be mitigated when PM peak hour LOS falls below LOS E
2. State-owned Regionally Significant State Highways (PSRC)
PSRC, in cooperation with WSDOT, has adopted LOS standards for Regionally Significant State Highways (non-HSS). (ref. 13) These are highways not deemed to be of statewide significance by the Washington State Transportation Commission. The non-HSS LOS varies depending on the intensity/form of development in an area. “Inner urban areas” are mapped where LOS “E-mitigated” would apply to non-HSS, and outer urban areas are mapped where LOS “D” would apply to non-HSS. For the remaining rural areas, a LOS “C” would apply. The LOS standards for non-HSS are for a p.m. peak hour, with local agencies having the discretion to decide on the appropriate field and planning-level methodology.
3. State-owned Highways of Statewide Significance (WSDOT)
The Washington State Transportation Commission has adopted LOS standards for use by WSDOT in evaluating the performance of highways of statewide significance (HSS). (ref. (13) Compliance with HSS LOS standards is measured by WSDOT using a variety of methodologies based on the most current addition of the Highway Capacity Manual. The methodologies determine LOS based on volume-to-capacity relationships, travel speed and delay, and duration of congested conditions on a highway segment, intersection, or at an interchange.
4. Existing Arterial Level of Service Deficiencies
RCW 82.02.050(4)(a), in conjunction with the GMA (RCW 36.70A.070), requires the county to identify “deficiencies in public facilities serving existing development and the means by which existing deficiencies will be eliminated within a reasonable time period”.
The county has established technical procedures for determining when an arterial is deficient relative to adopted LOS standards as discussed in Chapter III. Implementation Measures. It formally identifies an arterial deficiency when it declares that an arterial unit is in arrears because its operating speed is below the adopted LOS standard for that particular class of arterial. As of the publication date of this transportation element, no arterial units are identified as being in arrears and consequently no existing arterial deficiencies are identified in this TE.
5. Road Condition Audits
A Road Condition Audit (RCA) is another basis for identifying arterial deficiencies. An RCA determines if deficient conditions exist that would affect the roadways ability to safely serve expected growth and development. Deficient conditions can exist on the current road system or be caused by a new development's traffic. While an RCA may identify deficient conditions anywhere on the arterials system, they are more likely in areas of the county experiencing intensive growth and development.
The RCA process employs a technical evaluation, professional engineer/management review board, and final evaluation by the county engineer to determine when and where deficient conditions exist. Deficiencies identified by an RCA can include but are not limited to: sight distance; alignment; geometrics (e.g., lane width and shoulders); and traffic control. The public works department relies on a process that is informed by citizen comments, operational concerns, and land development review to identify locations of concern.
Deficient conditions can jeopardize the safety of road users, including non-automotive users. Mitigation is required if a new development is found to impact an RCA identified deficiency. Improvements to address the deficient conditions must be under contract prior to issuance of a building permit, and the improvements must be completed and accepted prior to issuance of a certificate of occupancy.
Roads that do not meet current design standards are common in all counties and cities and are generally not safety or operational problems. The public works department routinely funds and constructs operational and safety improvements before a deficient conditions exists.
C. Local Transit Level of Service Guidelines
Transit service is expected to play a much greater role in the county’s future transportation system. Transit, roadway infrastructure, and land use patterns interact, each influencing the other’s effectiveness. In order to accommodate and enhance transit LOS, land development and some of the county’s arterials within urban areas will need to be compatible with services provided by Community Transit, Everett Transit and Sound Transit. Community Transit, the primary supplier of local transit service in unincorporated Snohomish County, has adopted service guidelines in its 2011 Long-Range Transit Plan for appropriate transit service levels as it relates to land use, populations and employment density, infrastructure, and travel demand. (ref. 14) Table 7 shows these guidelines. Core service includes the Swift BRT service as well as other frequent routes on transit emphasis corridors. Community-based service feeds the core routes and connects urban, suburban, and rural areas.
Transit Emphasis Corridors/Core Service |
Community-Based Service |
|||
---|---|---|---|---|
Swift BRT |
Corridor Service |
Local Routes |
Rural Routes |
|
Travel Time |
No more than 30% greater than auto drive time |
No more than 50% greater than auto drive time |
No guideline |
No guideline |
Frequency: Peak/Off Peak |
5-10 min/10-20 min |
10-15 min/15-30 min |
20-30 min/30-60 min |
60+ minutes |
Station/Stop Spacing |
0.75 miles or greater |
0.10 – 0.75 miles |
0.10 – 0.50 miles |
0.10 – 1 miles |
Directness |
Straight on corridor with few direction changes |
Straight on corridor with few direction changes |
Many direction changes as warranted by demand |
Many direction changes as warranted by demand |
Transit Priority Infrastructure |
Required: Dedicated lane (BAT or better), signal priority, queue jump lanes, consolidated driveways |
Desired: Dedicated lane (BAT or better), signal priority, queue jump lanes, consolidated driveways |
No guideline |
No guideline |
Street Type |
Arterial/Highway |
Arterial/Highway |
Arterial/Collector |
Arterial/Collector |
Off-Street Parking |
Limited Supply |
Limited Supply |
No guideline |
No guideline |
Land Use |
Mixed-use; Major trip generators within ¼ mile of station. |
Mixed-use; Major trip generators within ¼ mile of station. |
Residential and lower-density employment |
Rural |
Density |
30+ person or jobs per acre within ½ mile of station |
30+ person or jobs per acre within ½ mile of station |
15+ persons/jobs per acre within ½ mile of stop |
Rural |
Pedestrian Connectivity |
Complete pedestrian network within ½ mile of route |
Complete pedestrian network within ¼ to ½ mile of route |
Complete pedestrian network within ¼ mile of bus stop |
Complete pedestrian network within ¼ mile of bus stop |
D. Intergovernmental Coordination and Impacts on Adjacent Jurisdictions
Intergovernmental coordination among county, city, state and transit agencies is needed to deal with the cross-jurisdictional impacts of the various land use and transportation plans (RCW 36.70A.070(6)(d)). The CWPPs for transportation provide a general framework for coordination that will help to understand and deal with cross-jurisdictional impacts. The CWPPs emphasize use of interlocal or intergovernmental agreements to establish strong and effective coordination among government agencies. CWPPs call for interlocal agreements that:
•define procedures and standards for mitigating traffic impacts;
•encourage sharing of improvement and debt costs for transportation facilities, services and maintenance;
•encourage joint development and plan review teams for major projects having impacts across jurisdictional boundaries;
•promote compatible design and LOS standards;
•allow sharing of development impact mitigation where a project's impacts extend across jurisdictional boundaries;
•Provide for integrated design of transportation facilities in designated urban growth centers to encourage transit-oriented land uses and nonmotorized modes of travel.
•help set priorities and programming for state, regional, and local facilities and services consistent with the GMA and Federal Transportation Legislation; and
•help establish consistent rules and procedures for environmental mitigation.
The General Policy Plan (GPP), consistent with the CWPPs, requires the county to "plan, develop and maintain transportation systems through intergovernmental coordination." The technical process undertaken to produce this TE included travel forecasts and modeling to identify specific roadway projects that support county land use and transportation planning. The intent here is to advise the state and cities where the county’s land use and transportation plans had significant impact on their transportation facilities and services to warrant funding and programming of a particular improvement. Chapter IV. Recommended Transportation Improvements contains sections which itemize state, city and transit provider improvements that support the county's plans, and also provides an indication of the county's priority preferences.