The objective of this project was to devise a conceptually simple tool that operationalized the complex relationship between land use and travel behavior. The TELUMI is a set of maps that depicts how the region’s urban form affects overall transportation system efficiency. Nine map layers represent the effects of individual land-use variables on transportation efficiency. They include density (residential and employment), mix of uses (shopping and school traffic, the presence of neighborhood centers (NC)), network connectivity (block size), parking supply (amount of parking at grade), pedestrian environment (slopes), and affordable housing. The tenth layer is a composite index, which takes into account the relative effects of each of the nine variables on transportation efficiency, based on a statistical analysis that modeled the relationship between the land-use variables and King County bus ridership.
Each land-use variable is mapped by using three categories, which define zones of high, latent, and low transportation efficiency (TE). High TE values correspond to many convenient transportation options, including transit, non-motorized, and other non-SOV travel options. Low TE corresponds to few transportation options beyond SOV travel. Latent TE indicates that travel options remain limited, but that land-use conditions in these zones are favorable enough to permit easy and effective increases in future travel options—either via transportation system investments, demand management or other programmatic actions, or land-use changes.
The visual dimension of the TELUMI’s maps make the tool an attractive means of communication with lay audiences, while its quantitative capabilities can speak to transportation and urban planning professionals. While the TELUMI now shows how to rate areas of the Puget Sound for their existing transportation efficiency, it can and should also be used to set goals for future transportation efficiency and to monitor progress over time. Changes in the values of land-use variables can be assessed in terms of their impact on the region’s overall transportation efficiency.