Level of Service, the Wrong Performance Measure

Lara Fishbane, Joseph Kane, and Adie Tomer of Brookings take a closer look at the level of service measure and the problems its use causes. LOS essentially measures congestion, but it also guides transportation planning as decision makers, planners, and other stakeholders work to improve LOS scores.

When LOS is used in efforts to address congestion, the solution too often is to build more roads, say Fishbane, Kane, and Tomer. The results are sprawl and transportation networks that decimate communities and privilege cars over other modes. "In short, the auto-centric development LOS makes possible has become one of the greatest obstacles to transportation choice and access, economic agglomeration, and environmental resilience."

They argue that different measures are needed — for example, multimodal measures and those that consider vehicle miles traveled instead of LOS. "Decreasing reliance on LOS also means introducing measures that don’t lead with transportation use, but instead with measures related to economic, social, and environmental outcomes," point out Fishbane, Kane, and Tomer.

In addition, they urge a shift away from a supply focus, which supports LOS, to one on travel demand. The result, they say, will be a better understanding of why people travel, how transportation systems can better serve users, and ways travel behavior can be changed.