Vigil-Agrimis (VAI) is assisting Portland Parks and Recreation (PP&R) with the final design of a backcountry trail network in Marquam Nature Park adjacent to Oregon Health & Science University (OHSU). The proposed trail system includes approximately 2.5 miles of Type A (High Challenge) hiking trails that cross multiple creek drainages. Prior to this phase of work, VAI assessed the feasibility of a proposed trail network for the park, developed during a 2007 planning and public involvement process. VAI’s scope of work for this phase includes: trail layout design, grading, drainage, tree protection, erosion control, bridge design, environmental permitting, land use permitting, local building permit applications, and construction bid documents.

Marquam Nature Park is steep and heavily forested, and the entire study area is in an Environmental Protection Zone, as classified by the City of Portland. VAI considered each trail segment for its impacts on hydrology and habitat, safety and maintenance issues, scenic impacts, pedestrian and recreation connections, natural places accessibility, permitting issues, and an opinion of construction costs. VAI based this assessment on field visits, a preliminary grading study in AutoCAD Civil3D, and our review of Portland’s Planning and Zoning code.

VAI developed and tested profiles for each trail segment using AutoCAD Civil3D. This allowed us to rapidly develop alternative trail alignments that did not exceed PP&R’s 15% grade threshold. We also assessed potential bridge locations and bridge lengths to help determine construction costs and permitting impacts.

Following the development of trail alignments, VAI produced graphics for a public meeting and assisted City staff at the meeting by addressing questions regarding trail layout, design, and permitting. VAI also worked with City staff to develop an efficient and effective scope of work for the survey team. This enabled the survey team to focus their efforts on the sensitive natural areas that have strict permitting requirements and require detailed documentation of existing conditions.