Central City Streetcar

Portland, Oregon

HWA GeoSciences Inc. provided environmental services and geotechnical design services for the four-mile long alignment in downtown Portland. The streetcar project extends from Portland State University to the Good Samaritan Hospital, connecting downtown residential, commercial and retail areas. In addition, the proposed track intersects Portland's light rail line.

HWA managed the preparation of an environmental reconnaissance study (similar in scope to a NEPA environmental assessment) which included impacts, alternatives, and mitigation measures for soils, air quality, water resources, wildlife, transportation, aesthetics, etc. HWA conducted a hazardous materials assessment of the alignment, identifying areas of potential contamination which might affect construction of the project. The assessment also included a noise and vibration analysis, which identified noise and vibration impacts and mitigation measures along the proposed railway alignment.

HWA performed subsurface explorations along the alignment to evaluate soil and groundwater conditions. HWA also prepared a geotechnical report summarizing our findings and presenting recommendations for the design and construction of the proposed track, a maintenance building, caternary pole foundations (poles for the electricity-driven streetcar), site seismicity and general earthwork. Challenges included designing building foundations and track slab to be supported on compressible fill and alluvial deposits, and designing caternary pole foundations (diameters and embedments) around numerous utility constraints.