Introduction

Project background
PBOT is preparing to take advantage of an opportunity to partner with Washington County in sharing the cost to improve a shared intersection: SW Multnomah Boulevard & Garden Home Road. 

Multi-jurisdictional coordination
Although PBOT is the road authority for SW Garden Home east of SW 71st, this location is in Washington County and PBOT is coordinating with the following entities:
  • Washington County Department of Land Use and Transportation
  • City of Beaverton (Transportation)
  • Beaverton School District
  • TriMet
  • City of Portland Bureau of Environmental Services
  • Portland Fire and Rescue
  • Tualatin Valley Fire & Rescue

Summary of proposed changes
Installing roundabout or traffic signal based on input from residents, cost, and technical feasibility.

On SW Garden Home rd between SW 69th – SW 71st, PBOT is proposing the following cross-section (south to north): 5’ bike lane, 2’ buffer, three 10’ motor vehicle lanes (includes center turn lane), 2’ buffer, 5’ bike lane, and 10’ curb tight sidewalk.

For SW 69th (south leg), PBOT is proposing to maintain only bicycle and pedestrian access on 69th (south leg).  Motor vehicle traffic would use SW 67th.  Our expected outcomes include lowering the risks of crashes by serving fewer legs at the intersection and more efficient traffic flow through the intersection with a longer green signal on the main arterial.  

For SW 69th (north leg),the proposal is specific to whether PBOT moves forward with a roundabout or traffic signal.
  • For the roundabout option, PBOT is proposing allowing right turn in and right turn out from 69th only.  Traffic coming out from 69th and wanting to head east could still turn right and circle around the roundabout to head east.
  • For the traffic signal option, PBOT is proposing allowing right turn in only and eliminating access from 69th onto Multnomah.  This proposal is grounded in the fact that 69th may be too close to the traffic signal and may pose a safety risk.

Completing sidewalk infill (10' wide) on SW Garden Home rd between SW 69th-SW 71st on north side of street.

Installing crosswalks and American Disabilities Act compliant curb ramps on all legs of the intersection.

Enhancing current bicycle facilities by providing a buffer between cars and bikes.

Improving transit speeds through transit signal priority or street design.


Survey background
This survey seeks to gain resident input surrounding project elements.  A key component of the survey is for PBOT to gain a better understanding of which option community members support: roundabout or traffic signal.  There are various advantages, trade-offs, and cost differences between these two options.

Information about traffic signals
Cost estimate:  $3.5-$5.5 million 

Many Portlanders are familiar with traffic signals as they exist throughout the city.  Traffic signal option has a lower upfront cost due to fewer stormwater, grading, and private property impacts.
 
Information about roundabouts

Cost estimate:  $4.5-$6.5 million 
Additional info on next page

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