Arboretum Loop Trail grand opening in April

Seattle Parks and Recreation uses $7.8M in mitigation funds to open up more of the park to visitors

Arboretum Loop Trail grand opening in April

Arboretum Loop Trail grand opening in April

The Washington Park Arboretum Loop Trail took many years to complete, and many more will be spent in the future to ensure the trees and wetlands around it continue to grow and thrive.

“When we laid out the trail in the arboretum, we actually laid out the trail six times,” said Garrett Farrell, projects manager with Seattle Parks and Recreation.

After quietly opening the new trail that runs from East Madison Street to the Graham Visitors Center back on Nov. 10, a grand opening celebration will be held noon to 3 p.m. Sunday, April 8. A vine-cutting ceremony will officially open the Loop Trail at 1 p.m., and takes place in the Birch Parking Lot at Lake Washington Boulevard and East Interlaken Avenue.

The Washington Park Arboretum takes many hands to care for, including the University of Washington, which maintains an impressive botanical collection there, and the Arboretum Foundation, which provides family programming, advocacy and volunteers to steward the park.

“One of the main ideas here is we were trying to make the collection more accessible in that part of the arboretum,” said Niall Dunne, Arboretum Foundation communications manager.

The trail was planned for in the arboretum’s 2001 master plan, and the $7.8 million that ended up funding the project came from mitigation funds provided by the Washington State Department of Transportation in connection with its State Route 520 Bridge replacement project.

“We did a lot at the negotiation end of things to get that money for the arboretum,” Dunne said, “because our partners are sort of limited in what they can do for the advocacy side.”

Creating a 1.2-mile paved trail from East Madison Street to the existing Arboretum Drive was a delicate task, and one that required minimizing tree removals and putting many back in along the new trail and restored Arboretum Creek wetlands.

“When I started this, so much of that creek was in a pipe,” said Farrell, and now huge areas of wetlands have been restored. “We can’t turn the clock back, and there are certain parts of Arboretum Creek that are still in a pipe or a culvert.”

Restoring aquatic habitats inside the Washington Park Arboretum and along the trail, including more plantings, is expected to continue for decades.

“I still have huge areas of plantings that are under federal permits,” Farrell said, “and wetlands that are under the Army Corps of Engineers.”

Farrell said there was a lot of concern about preserving both UW’s collection and native trees before the trail’s construction began.

“Part of the whole planning and execution of the project was the tree collection,” Dunne said, “and there’s been a lot said and written about the care put into making sure the impacts were minimal.”

Prior to starting on the trail or touching a tree, Farrell said, there was a three-year period of invasive species removals and new plantings at the Washington Park Playfield. 

Around 137 trees were eventually removed for the trail. Many of those that could not be moved elsewhere had tissue samples or seeds taken and planted in other parts of the arboretum.

“Most of those trees removed are what you see around the banks of the stream or in the wetlands,” Farrell said.

The trail winds around native collections, connecting to Arboretum Drive for a 2.5-mile path open year-round. Farrell said he’s very happy with how the 18 benches turned out, designed in the style of the 1939 World’s Fair Bench developed in New York.

Dunne said people can see where UW has been putting in new plantings along the trail, and the Arboretum Foundation is working with the university to raise funds for a new education building planned next to the visitor center. The plantings in the wetlands, which are mostly native perennials, was done primarily by the city contractor as part of the required mitigation for SR 520.

Among the festivities that will take place during the April 8 grand opening will be a Husky Marching Band Drumline march on the trail.

“We keep adding little things to it,” Dunne said of the grand opening. “We seem to be getting a lot of interest from folks.”

Dunne and Farrell both note the popularity of the new Arboretum Loop Trail is evident to anyone using it on a sunny day, or even when weather is less than fair.

“There’s a lot of families with strollers and people walking their dogs and riding their bicycles,” Dunne said. “The key thing we hoped would happen was creating this opportunity for recreation and exercise in the arboretum.”

Farrell said now that the state capital budget has passed, funding is available for him to begin work on improving the Waterfront Trail at the Washington Park Arboretum, including addressing issues related to seasonal high water levels that cause occasional closures there.