Arboretum Loop Trail nears construction start

By Audrey Wennblom

An artist's rendering of one of the bridges on the Arboretum Loop Trail. Image courtesy the Berger Partnership
An artist’s rendering of one of the bridges on the Arboretum Loop Trail. Image courtesy the Berger Partnership

At long last, the Arboretum Loop Trail (ALT) appears to be just a few months away from the start of construction. “Right now, it looks like the tentative start date would be late spring 2015,” said Raymond J. Larson, Curator of Living Collections for the UW Botanic Gardens. “The idea is to start after most of the rain has passed and to do construction over the drier months.’’

Depending on the the bids received, Larson said the project may be done in two phases. The first phase would be from E. Madison Street to the Boyer/Birch parking lot along E. Lake Washington Blvd. (across from the Holly Collection), he said. The second phase, in 2016, would be from the Birch Lot to the Graham Visitors Center. Larson said, however, that it could also happen all at once. “It depends on a variety of factors,” he said, “and the contractor selected.”

But before any work begins, “the first thing we will do in the field is contract out the transplanting of collections,” said David Zuckerman, Horticulture Manager for the UWBG. “This work will begin as early as this fall sometime, even if it’s just root pruning,” he said.

The ALT is expected to have several benefits for the Arboretum.  “First, it will get people into areas of the arboretum that are currently less well known and visited,” Larson said.  Most people don’t make it to the viburnum collection or know where it is, and don’t get through the Flats (where birches, poplars and the creek is) much of the year because the ground is too wet and there are no trails there, Larson said.  “The ALT will also open up a new route through the largely undeveloped southern hillside across from the Japanese Garden and will provide another way to access the Pacific Connections Gardens,” said Larson.  That is an area currently difficult to navigate and where it is easy to get disoriented (especially for new or occasional visitors), Larson said. Access is going to be much better and the park should feel bigger, he said.

The collections themselves will also benefit. “We will have many new planting areas that will be accessible and viewable,” Larson said.  Some of these will anticipate future phases of the Pacific Connections China and Chile ecogeographic gardens.  “Where the trail crosses through these areas we will be planting plants from those areas along the way,” Larson said.  Other areas will see the addition of a diversity of new plantings that strengthen existing collections (viburnums, oaks, rhododendrons, etc.). “There are going to be a lot of new plants going in, and areas with a lot of ivy and invasives will be refreshed,” he said.

All of this adds up to a better visitor experience—finding your way more clearly as you navigate through the gardens. The north end will be enhanced with better sightlines and a clearer, more obvious connection to the Graham Visitors Center, where the trail forms a loop with Arboretum Drive E, Larson said.  It should feel less hidden and more welcoming.  Some existing blind spots will be improved and in general areas should feel refreshed.  “We think this will be a popular walking and bicycling trail, and the loop connection should help people better experience more of the park,” Larson said.

More Information

Seattle Department of Planning and Development trail project page

Seattle Parks and Recreation trail project page