Modern traffic mitigation for development in cities: Moving beyond LOS

October 29, 2018

Cities exist to provide people and firms with access to goods, services, employment, and other people. A mark of a city’s success is the clustering of complementary land uses to residents’ and businesses’ mutual benefit; the more people and activities within reach of each other, the greater the benefit from this accessibility.

But new development can bring concerns about additional motor vehicle traffic and congestion. Conventional mitigation estimates the motor vehicle trips from a proposed land use in a popular location—often exacerbating the number of trips through requirements for off-street parking—then requires the new land use to “mitigate” the resultant traffic impact through roadway capacity increases in order to maintain auto level of service (LOS).

This conventional approach has significant problems, including:

  • Placing expensive burdens on desirable new land uses, possibly pushing them into less-accessible locations.
  • Inducing more traffic and the resulting environmental, safety, livability, and personal cost problems.
  • Reducing the ability of travelers to use non-auto modes because of impediments posed by wider, busier roadways.
  • In short, the conventional approach degrades the accessibility of cities, undermining their fundamental ability to function. Fortunately the conventional approach can now be supplanted with better practice.

Spurred by state legislation, cities in California are replacing LOS-based mitigation with methods based on a land use’s effect on VMT across the system. On this webinar we’ll hear about some approaches to non-LOS-based mitigation from California and elsewhere. These methods are practical and portable to non-California cities and states.

The city of San Jose has been one of the leaders in implementing VMT as a measure to evaluate the transportation impacts of new projects. San Jose will cover some of their early efforts to make this transition from LOS to VMT, shifting from a car-oriented metric toward something that takes into account different modes and service models.

SSTI used examples from San Jose and other cities around the country to develop a program for cities to embed these modern mitigation methods into the city development review.

Join Eric Sundquist, SSTI Director; Ramses Madou, Transportation Planner with San Jose Department of Transportation; and moderator Beth Osborne, Senior Policy Advisor at Smart Growth America, for a lively discussion of the opportunities and challenges of moving from LOS to VMT and what steps are needed to make this shift work.

Download the slides from this webinar.