Cover image
Apr 18, 2019
Principal Investigator: Aaron Golub, Portland State University
Learn more about this research by viewing the Executive Summary and the full Final Report on the Project Overview page, or watching a recording of the January 2019 webinar.

Since 1994, every Federal agency must develop a strategy for addressing “environmental justice” (EJ) – the disproportionately adverse human health or environmental effects on low-income and minority populations (sometimes called “EJ Populations”). In transportation planning this means including those communities' voices in the planning process, and evaluating the social impacts early on in the planning and project development process.

But what happens if EJ Populations move or grow during the sometimes decade-long project development process?

"If you're in a community that is changing, can you rely on forecasting to look ahead and have a detailed view of EJ impacts into the...

Read more
Dec 03, 2014

View slides

The video begins at 8:13.


The Americans with Disabilities Act (ADA) of 1990 provides comprehensive civil right protections to individuals with disabilities. ADA Title II requires every state and local government to prepare a self-evaluation plan to identify program access issues. From this, a transition plan is required showing policies and practices to achieve a barrier free environment. Although transition plans are required by the ADA, few cities have complied due to the high cost and complexity of conducting an accurate grade, cross-slope, and slab-to-slab faulting inventory assessment of their pedestrian facilities. Public works departments now are facing increased pressure to determine cost-effective and efficient methods for compliance with ADA accessibility standards. Failure to properly manage ADA compliance has proven costly to many cities throughout the country due to an increasing amount of litigation. The Bellevue Transportation Department decided to take a progressive approach to managing ADA compliance under a pilot program made possible by the Federal Highway Administration. The Ultra-Light Inertial Profiler (ULIP) is a specially-equipped Segway with an inertial profiling hardware sensor box that includes a displacement measurement...

Read more
Dec 06, 2010

Why build bigger when you can get more out of what you already have? That’s a question agencies across the country have considered as they face costly expansions of roadway systems or are unwilling or unable to keep building.

Adaptive signal control technologies offer the promise of reducing congestion, smoothing traffic flow and improving safety on existing roads. The Federal Highway Administration has been holding regional summits about this technology across the country.

Metro hosted one of the summits Dec. 1 at the Intelligent Transportation Systems (ITS) laboratory at Portland State University. Federal Highway Administration ITS specialists Paul Olson and James Colyar gave an overview of the technology, which can:

  • Automatically adapt to changes in traffic
  • Improve travel time reliability
  • Reduce congestion and fuel consumption
  • Monitor and respond to gaps in traffic signal operations
  • Reduce complaints agencies get about bad signal timing

Adaptive technologies use data from sensors to adjust traffic lights, keeping the green light for as long as conditions warrant. The process updates in a few minutes what traditional signal retiming might accomplish only every few years.

The technology is best suited for arterials that receive variable or unpredictable traffic. On these roads, the signals can improve travel time, emissions and fuel consumption by 10 percent or more. Where signal timing has been...

Read more