In 1979, JGM was a key member of the consultant team that created preliminary designs for I-90 on Mercer Island . JGM developed the landscape concepts for new park facilities to be constructed on 13 acres of lidded structures over the freeway. The firm was responsible for pedestrian and bike trail alignments, acoustical control, pedestrian circulation, concrete finishes and configuration of planting areas. The community and trail linkages were created to provide continuity of pedestrian movement while minimizing the highway’s visual and acoustical impacts.

In 1985, the firm was retained as a prime consultant to prepare the I-90 Landscape and Trail Corridor Master Plan for all of Mercer Island . This effort involved inventory, analysis, value engineering, as well as development of a plant palette, planting and irrigation plans and a comprehensive landscape management plan. JGM worked with the structural engineers in the design of the lids and contouring of soil depths to accommodate tree plantings and lawn areas. JGM was subsequently retained to complete the final design documents for the 3.2-mile corridor.

JGM received a National ASLA Merit Award and National Merit Award for Design in Transportation from the U.S. Department of Transportation and a Presidential Design Achievement Award from the National Endowment for the Arts.

David McNeal, FASLA, was the principal-in-charge and led the design team. Ted Wall , ASLA, was the project manager.