The existing cross section of NE 238th Drive had narrow travel lanes, no bicycle lanes, one narrow sidewalk, and steep topography with new development along the corridor. The road is also heavily used by freight as it connects I-84 to the north with cities in eastern Multnomah County and with US-26 to the south. These conditions created uncomfortable and unsafe conditions for active transportation users. In addition, an intermittent patchwork of stormwater conveyance provided limited stormwater management.
To improve multimodal safety and connectivity between I-84 and the developing industrial and residential areas south of Wood Village, this project widened NE 238th Drive and added pedestrian and bicycle facilities. In addition to pavement widening, the project included a new fill retaining wall, a shared use path on both sides of the road, new illumination, signing, striping, and stormwater facilities, which included detention, treatment, and conveyance facilities.
Parametrix worked with Multnomah County staff to develop cross sections options, assessed benefits and tradeoffs to evaluate options, and presented the results in public meetings to narrow and select a preferred cross section. The result was collective buy-in on a balanced cross section that met all user needs.
Limited right-of-way created a challenge for treating and detaining stormwater runoff. The team evaluated different treatment facilities for footprint, cost, and long-term maintenance. The selected option combines planter swales and a small infiltration pond. Underground vaults beneath the road surface were selected as the least-impactful, lowest-cost stormwater detention alternative.
In addition to alternatives analysis, Parametrix provided survey, design and engineering, public outreach support, environmental approvals, permitting, NEPA closeout documentation, and engineering support during construction.