jogger on a road next to rock wall in a forested area yellow bike next to gravel trail bike wheel with gravel underneath park bench next to road with rock wall in distance bridge with drain pipe underneath surrounded by rock gravel trail through woods rock wall next to road in wooded area


Date: April 2016-April 2018


The Washington Park Arboretum is a 230-acre special-purpose park with the purpose of educating and providing recreation. Seattle Parks and Recreations (SPR) added rock walls and irrigation ditches lining the new multi-use/loop trail. The loop trail is a $7.8 million portion of a 20-year, $45 million master plan for the arboretum.

Washington Rock supplied materials to Ohno Construction and AAA Contractors for the project.


230 Tons of 2-Man Landscape Rock
150 Tons of 3-Man Landscape Rock
225 Tons of 2"-4" Quarry Spalls
Trail Mix
5/8" Minus


Washington Rock's Landscape Rock and Quarry Spalls were used to create the sprawling rock walls throughout the new 1.2-mile trail. The rockery was an important aspect of the new trail. The plans originally called for concrete walls, but the rock walls allowed the arboretum to save money during a construction boom.

Our Trail Mix gravel and 5/8" Minus gravel have also been used to pave the hiking trails. The distinct blue color of our rock contrasts beautifully with the newly restored forest and wetland areas.

Portions of the rock wall were photographed for a Seattle Times article and UW News.