SR 9 - SR 204 Intersection Improvements - Design options

The design options below are representative of a year-long collaborative effort between the project team, the Lake Stevens community and key stakeholders (referred to as the Stakeholder Advisory Group) to find a new design option for the SR 9/SR 204 intersection to meet the needs of a growing region. The collaborative process began in August 2016 with identifying goals that could be achieved with a new intersection design. Design concepts were evaluated together with the Stakeholder Advisory Group and through traffic analysis to make sure they could potentially meet the goals set by the project team and Stakeholder Advisory Group. After evaluating many different intersection design concepts, the Stakeholder Advisory Group recommended the preferred alternative; Concept E2b-v4.

 

SAG Recommended Preferred Alternative

Tight Diamond Interchange with Market Place Northeast Improvements (Concept E2b-v4)
This design concept was developed as a refinement of the previously developed design concept E2B. Four variations were developed as refinements of E2B. The SAG-recommended preferred alternative is referred to as E2B-v4. Variation E2B-v4 explored opening the Vernon Road cul-de-sac proposed in Concept E and keeps the current Vernon Road configuration. Concept E2B-V4 consists of the following elements:

This design concept was developed as a refinement of the previously developed design concept E2B. Four variations were developed as refinements of E2B. The SAG-recommended preferred alternative is referred to as E2B-v4. Variation E2B-v4 explored opening the Vernon Road cul-de-sac proposed in Concept E and keeps the current Vernon Road configuration. Concept E2B-V4 consists of the following elements:

  • A tight diamond interchange that grade-separates SR 9 beneath SR 204.
  • Improve capacity and operations at the SR 9/Market Place Northeast intersection by adding a through-lane on SR 9 in each direction.
  • Improve access from/to northbound SR 9 at 4th Street Northeast.
  • Modify the southbound SR 9/Vernon Road off-ramp as necessary for acceptable operations.
  • Improve operations at the entrance to Frontier Village by closing 92nd Avenue Northeast.
  • Improve the 7th Place Northeast, Vernon Road, and SR 204 intersection to enhance operations.
  • Improve the intersection at Vernon Road and North Davies Road intersection to improve traffic flow.
  • Provide bicycle and pedestrian pathway connectivity to businesses and transit.

Graphic: Concept E2B-v4

Concept E Refined Design Options
The below list of concepts was developed as refinements to Concept E during the second quarter of 2017. These refinements were key to reaching consensus on the preferred alternative design option E2B-v4.

Tight Diamond Interchange (Concept E2A)
This design concept is identical to Concept E, however refined for a two-lane SR 9 each way. A traffic analysis of the original Concept E showed no need or significant benefit for an added lane along SR 9.
Graphic: Concept E2A

Tight Diamond Interchange with Market Place Northeast Improvements (Concept E2B)
This design concept consists of a tight diamond interchange with a two-lane SR 9 (Concept E2A) and adding a through lane at the Market Place Northeast and SR 9 intersection in each direction.
Graphic: Concept E2B

Tight Diamond Interchange with Davies Half Interchange/Overpass (Concept E2C)
This design concept consists of tight diamond interchange with a two-lane SR 9 and includes an above grade Vernon/Davies half interchange over SR 9.
Graphic: Concept E2C

Tight Diamond Interchange with Market Place Northeast Improvements and Davies Half Interchange/Overpass (Concept E2D)
This design concept consists of a tight diamond interchange with a two-lane SR 9 and includes both the SR 9/Market Place Northeast intersection improvements (through-lane at Market Place Northeast and SR 9) and the above grade Vernon/Davies half interchange over SR 9.
Graphic: Concept E2D

 

Initial Design Option Refinements

The below list of concepts was refined from early concepts developed during the fourth quarter of 2016.

Local connectivity improvements (Concept B)
This option makes several improvements near the SR 9/SR 204 intersection, including a roundabout interchange at SR 9/SR 204 with SR 9 traveling under the roundabout to allow SR 9 traffic to flow straight through. The SR 9/SR 204 roundabout would be connected via new frontage roads to a new roundabout at the Vernon and Davies intersection. Traffic traveling to and from SR 9 to the south would use the SR 9/SR 204 roundabout, while traffic to and from SR 9 to the north would use the Vernon and Davies roundabout. A smaller roundabout would also be considered at 4th Street NE to provide full access from SR 9 to 4th Street NE. 
Graphic: Concept B

This design improves access to Frontier Village via 7th Street NE by adding a cul-de-sac at Vernon Road, closing off 92nd Avenue NE, and creating an opportunity to turn right off NB SR 9 to 4th Street NE and turn right from 4th Street NE onto NB SR 9. Village Way, a locally-used roadway into Frontier Village, is improved to provide access through Frontier Village to the SR 9/SR 204 intersection. 
Graphic: Concept C

Recessed ramp (Concept G2B)
This concept creates a direct connection from eastbound SR 204 to northbound SR 9 by constructing a ramp under SR 9 that begins on SR 204 west of 91st Avenue NE and continues along SR 204, re-emerging onto NB SR 9. The 91st Ave NE/SR 204 intersection stays at grade above the newly constructed connection on a bridge-like structure. The SR 9/SR 204 intersection is reconfigured, remaining at grade above the newly constructed connection. Other improvements include creating an opportunity to turn right off NB SR 9 to 4th Street NE and turn right from 4th Street NE onto NB SR 9, and improving Village Way as a local road through Frontier Village. 
Graphic: Concept G2B

Tight diamond interchange (Concept E)
This design concept lowers SR 9 below the interchange and adds a lane to SR 9 in both directions from south of Market Place NE to the interchange and north to Lundeen Parkway. The SR 9/SR 204 intersection stays at grade with four lanes of SR 9 (two lanes each way) under the intersection. Creates on- and off-ramps in both directions of SR 9 and updates the Vernon Road off-ramp. Other improvements include signalizing the intersections at the ends of the on and off ramps, creating an opportunity to turn right off NB SR 9 to 4th Street NE and turn right from 4th Street NE onto NB SR 9, and improving Village Way as a local road through Frontier Village. 
Graphic: Concept E

Roundabout interchange (Concept H)
This design concept is similar to the tight diamond interchange (Concept E), but does not add new lanes to SR 9. The SR 9/SR 204 intersection would be changed to an at-grade roundabout interchange with SR 9 traveling below the roundabout. This concept allows SR 9 traffic to flow through the interchange. On- and off-ramps are added in both directions of SR 9. Other improvements include creating an opportunity to turn right off NB SR 9 to 4th Street NE and turn right from 4th Street NE onto NB SR 9, and improving Village Way as a local road through Frontier Village. 
Graphic: Concept H