Case Study:

Tren Urbano

Conclusions

Further Development

The station-area walkability analysis described in this paper complements the regional accessibility analysis. The walkability index can be used to estimate the actual population served by transit. Current estimation methods assume that population is uniformly distributed throughout a TAZ, and that everyone within a given radius has access to the transit station. The walkability index can be used to refine this estimate to account for street networks that are not conducive to transit access.

The amount of population served by transit (by TAZ) might be incorporated into travel demand models to improve the ability of these models to predict transit ridership. It is further conceivable that with a high-quality GIS street network and a parcel-level land use database, the number of people or jobs within a five- or 10-minute walk of stations could be measured, rather than estimated based on an assumed uniform distribution of population. An example of such an analysis for a proposed LRT system in Orlando, Florida is shown in Jaskiewicz and Russ (1998).

Ultimately, the integration of micro-scale analysis techniques with regional travel demand models should serve to improve the accuracy of travel demand forecasting and to improve the usefulness of the resulting accessibility measures. This has been done in cities such as Portland, OR, which include a "Pedestrian Environment Factor" in their travel demand model. For additional discussion of the integration of micro-scale design variables into travel models, see Douglas (2000).

[TOP]