Comparative Effectiveness of Multi-Modal Alternatives in the Long Term

Focus Area



Air Quality, Environmental Process




Under $99k


Under 1 year

Research Idea Scope

There are several examples of metropolitan areas choosing not to build major transportation infrastructure for single-occupancy vehicles (SOVs) – Vancouver, B.C.; San Francisco, CA etc.  This study would be a comparative analysis of similar metropolitan areas – some of which have chosen to build major infrastructure for SOVs (and other transportation types), such as Boston’s “Big Dig”, and others who have chosen not to build major transportation infrastructure.  The study would determine appropriate comparative examples and critieria by which to make a useful comparison for cities currently considering alternatives to major transportation infrastructure, such as Seattle’s Alaskan Way Viaduct Project.  The results should be published as a comparative case study/ decision support tool.

Urgency and Payoff

The City of Seattle eliminated from the NEPA process the so-called “surface, transit I-5 improvements” alternative because it was deemed to not meet mobility and other needs.  Substantial support exists, however, among stakeholders in Seattle for the eliminated more multi-modal focused alternative.  The benefit of this study would be to help cities – such as Seattle – gain a better understanding of the consequences of not building major transportation infrastructure with a primary focus on Single Occupancy Vehicles.

Suggested By

Erik Peterson, Environmental Protection Agency

[email protected]