Washington Park Arboretum Loop Trail

Updated: August 6, 2019

Thank you, Seattle! This project is complete.


Move the master plan forward and provide enhanced circulation to maximize the Arboretum value to all communities of western Washington as a place of education, conservation and recreation.


This project provides a multi-use/loop trail from the intersection of East Madison through the Arboretum to the intersection of Foster Island Road and Lake Washington Boulevard. The addition of the 1.2 miles of paved multi-use trail creates a "loop" with the existing Arboretum Drive providing an accessible path for all visitors. The path will offer recreation opportunities and access to new parts of the Arboretum collection for all. The city received $7.8 million dollars from Washington State Department of Transportation. Seattle Parks and Recreation awarded the Berger Partnership the design contract after an RFP and interview process was conducted. The scope of work calls for a coordinated and phased construction of a multi-use trail system through the Washington Park Arboretum, a living museum of rare high value trees and plants. The contract work includes installation and maintenance of tree and plant protection, temporary erosion and sedimentation controls, temporary access issues and coordination for the Washington Park Arboretum, operations staff and visitors. The construction of a paved multi-use trail includes selective site demolition, specialty excavation by hand or air-spade, selective tree removal, excavation, grading, fill placement, paving, walls, bridges, storm drainage, utilities, parking, stream restoration, wetland restoration, site restoration, irrigation and planting. The work will be carefully controlled to limit the impacts. The project will:

  • Add 1.2 miles of paved multi use trail creating a "loop" with the existing Arboretum Drive providing recreation and access to the Arboretum collection
  • Remove 132 trees greater than 6" diameter, move 13 trees and propagate over 75 trees and large woody plants
  • Plant over 800 new trees throughout the Arboretum (a ratio of over 6:1 greatly exceeding the City of Seattle 2:1 tree replacement requirements)
  • Restore over 2.5 acres of wetland
  • Restore over 2 acres of forest around Lake Washington Playfield
  • Plant over 30,000 plantings for wetland, trail restoration, rain garden, groundcover and collections

The master plan for renewing the Washington Park Arboretum was adopted by City Council and the University of Washington Board of Regents in May 2001. The University, City and the Arboretum Foundation are working together to continue implementing the master plan.

Download the Arboretum Master Plan

Loop Trail Concept

Bridge Concept

Project Timeline

Fall 2018

Seattle Parks and Recreation, the University of Washington and contracted crews have been working along the new Loop Trail maintaining collection and the new wetland area plantings. There will be work over the coming months replanting areas of the wetland, repairing irrigation and addressing drainage issues.

Spring 2018

The new Loop Trail opened to cyclists and pedestrians in November 2017.  
The Grand Opening Celebration and ribbon cutting was held April 8, 2018 in the Arboretum. You can view the event poster here.

In the Arboretum, cyclists are welcome only on the new Loop Trail and other paved paths.
Please observe the 10 mph speed limit and yield to pedestrians.

Planting work and final construction work is ongoing with a few small tasks remaining along the mile of new trail.

October 2017

On Friday, October 27 crews will install a sleeve for a water line under Lake Washington Blvd. This work will require a drill rig, heavy truck equipment and a trailer. Staging of the equipment will happen in the Japanese Garden parking lot and work will occur between the stone cottage and Location 1 on the map.

We will not close Lake Washington Blvd to traffic but there will be short term impacts as we move equipment. The contractor will provide flagging and maintenance of traffic. We anticipate the track mounted drill rig to move into place along the Boulevard around 9:30 in the morning temporarily impacting traffic.  

On Friday, October 27 through Wednesday, November 1 the contractor will be placing soil on slopes from location 4 to location 5 on the map. Expect single lane closures and traffic delays as we move material and equipment.

September 2017

As of September 13th the contractor will have installed all the new paved trail asphalt. Concrete work at path entry points and paving in the Birch Lot will take place over the next two weeks. There will be intermittent lane impacts for brief periods (up to one hour) as we place concrete adjacent to roadways. Once all the paving is in place we will be working on signage, striping, fencing and other elements needed for us to open the new trail.

The Arboretum will remain open during construction. We will route users around the construction activities using notifications and signage for the project duration. We know construction can be difficult and we appreciate your patience as we construct these improvements to the Arboretum. The Arboretum Loop Trail is a multi-use path open to pedestrians and bicycles. Bicycles in the Arboretum are welcome on asphalt trails only; they must yield to pedestrians and follow the maximum speed limit of 10 mph. The construction will be more visible at the north end of the Arboretum near the Wilcox/Lynn Street Bridge and Foster Island Drive. Pedestrians crossing the Wilcox Bridge will encounter trail construction and may experience brief delays where the trail construction crosses existing paths. Earth movement to support trail work will also increase traffic on Foster Island Drive.

August 2017

Thanks to everyone for their patience with the closure of Foster Island Drive the night of the 17th, the intersection is paved. Work on Foster Island Drive will continue with traffic reduced to one lane at times while we place concrete at curb and ramp locations. The Intersection of Arboretum Drive and Foster Island Drive has transitioned to a three way stop, temporary stop signs are in place and permanent signs will be installed when the concrete work is complete.

May 2017

With the recent return of sunshine and dryer weather, the contractor has renewed their focus on Arboretum Creek and the restoration plantings. We will open the pedestrian access to Azalea Way across the Birch Lot on Saturday May 13, in time for Mother's Day. This will restore pedestrian access closed late in 2016. We will keep this access open for the remainder of the project.

Work adjacent to Foster Island Drive will be delayed while we focus on the stream and Birch Lot.

March 2017

Seattle Parks and Recreation (SPR), the University of Washington Botanic Gardens and the Arboretum Foundation are excited to announce that on Thursday, March 23, 2017, the first section of the new Arboretum Loop Trail in the Washington Park Arboretum opened to visitors.

The new path from 31st Ave. E and E Madison connects Arboretum visitors to Arboretum Dr. via the new paved asphalt path. Additionally, a short section of trail on the west side of Arboretum Dr. is open to pedestrians, connecting access up to the Pacific Connections Garden. The path is ready for use; landscape and other work elements will continue into the spring.

December 2016

The contractor has made great progress and is approaching the half way point of the project. Crews worked through the wettest October on record and have completed paving of new pathway from 31st Ave. E / E Madison to the Birch Lot. Cold temperatures have slowed the concrete work in the street on 31st Ave. E.  Please see the construction information document below. Our goal is to open a section of trail by early 2017.

September 2016

On Monday Sept., 26, Ohno Construction will begin to tear up and replace the south end of Arboretum Drive E.   This access point will be closed through October 15 2016 to build a key connection for the new loop trail.  Bicycle traffic will need to continue down lake Washington Boulevard E and pedestrians will need to travel to the Wilcox Bridge at Lynn Street to access the Arboretum.   This short notice is a response to a scheduling opportunity with a subcontractor that will allow us to complete a key section of the trail and help us get sections open to the public ahead of schedule.

The Arboretum remains open during construction and we ask visitors to follow detour routes. We know construction can be difficult and we appreciate your patience as we construct these improvements to the Arboretum.

July 2016

The contractor is installing rock walls, irrigation and will begin piling and concrete work for new walls and bridges in July. Work will also begin to open up Arboretum Creek .

June 2016

Tree removal work has been completed and earthwork is underway. The logs stored in the Birch Lot will be used in the stream and wetland restoration work. When we open up the creek in the coming weeks access across the Birch Lot will be cut off and pedestrians from both Azalea Way and the Japanese Garden will be routed up to the Wilcox Bridge or down to the south end of Arboretum Drive to cross Lake Washington Boulevard.

April 2016

The Contractor, Ohno Construction has mobilized to the site and started surveying, installing tree protection fencing and erosion control. Tree removals, earthwork and clearing will begin in April within the limits of the trail work. 

January - March 2016

The re-bid project was awarded to Ohno Construction. The notice to proceed was issued to the contractor on March 7, 2016.

November - December 2015

Seattle Parks and Recreation is re bidding the Multi-Use/Loop Trail in the Arboretum . The project Advertised November 23, 2015 and bids will open December 16, 2015.

July - August 2015

Seattle Parks and Recreation advertised Multi-Use/Loop Trail in the Arboretum for public bid July 29 2015, Bid opening is scheduled for August 19, 2015. Seattle Parks encourages all interested parties to visit the electronic bidding website to view the complete plans and specifications. Together with our partners the University of Washington and the Arboretum Foundation, we look forward to the bid openings.

May - June 2015

Parks, the Green Seattle Partnership and contractor Applied Ecology are working to remove invasive plants around Lake Washington Playfield at the south end of the Arboretum to prepare the area for tree planting this fall. Two trees will be planted for every tree removed as part of the Multi-use/Loop Trail project.

March - April 2015

Thank you to all who attended the meeting in January. Parks and the design team are working to complete permitting and finalize the construction documents. Parks and the University Of Washington are working to begin moving and propagating collection plantings.

January 2015

Parks and the design team are working to complete permitting and finalize the construction documents. Parks and the University Of Washington are working to begin moving and propagating collection plantings.

October 2014

The design team is working with our partners at the University of Washington to complete construction documents for bidding this winter.

The final design development plan was presented at the Multi-Use Trail project's final public meeting on February 27, 2014. Thank you to those who have participated in the public process for the project.

The multi-use trail was identified in the Arboretum master plan that was adopted in 2000. The trail was identified as a way to enhance the visitor experience of Washington Park Arboretum. Intended for use by both pedestrians and bicyclists, the curving path is designed to preserve vegetation and control speed.

The Berger Partnership was awarded the design contract after Parks conducted a Request for Proposal (RFP) and interview process. Construction is anticipated to commence in 2015.

This project initially provided scoping and conceptual design for a redeveloped North Entry to Washington Park Arboretum and a multi-use trail from the intersection of East Madison to the North Entry and the Montlake and University neighborhoods beyond. The Consultant Selection Committee recommended that the Berger Partnership be hired to provide design services for the project and Parks moved forward with that recommendation.

Meetings for the design of the North Entry and Multi-use Trail were held in 2011. The community provided input to assist the designers in developing a preferred alternative.

In June 2013 City Council approved $7.8 million from WSDOT to fund implementation of the multi-use trail, which does not include the North Entry Project. The Arboretum Botanical Gardens Committee held a well attended press conference to announce this funding in January 2013. Final design and permitting will take place in 2014 and construction is expected to start in 2015.

Community Participation

See our Public Process Through June 2015 document for a synopsis of the project and our outreach efforts.