Trolley Trail, Milwaukie, Oregon


As part of Harper Houf Peterson Righellis’s (HHPR’s) team, GeoDesign provided geotechnical and environmental engineering services for the six-mile ODOT-funded Trolley Trail.

The Trolley Trail is the name for the historic Portland Traction Company streetcar line right-of-way that stretches between the cities of Milwaukie and Gladstone.* The project, a joint undertaking  between North Clackamas Parks & Recreation and regional government Metro, involved developing the right-of-way for a 10- to 12-foot-wide multi-use trail.

Our geotechnical scope included completing borings in areas where cut and fill walls were proposed. Additionally, we conducted infiltration testing and shallow pit explorations to evaluate subgrade conditions and better establish required site stripping and clearing. Environmental work included surface soil sampling and additional support services to address the disposal of soil. The project was constructed in 2012.


Through our work with HHPR’s team, we helped turn a once-abandoned historic right-of-way into a six-mile trail that is now enjoyed by cyclists and pedestrians throughout the Portland metro area.


Infiltration testing, shallow pit exploration, borings, surface soil sampling

*See HHPR’s Trolley Trail site for historic photos of the Portland Traction Company streetcar line.

*photos courtesy of HHPR