Assessing intercity commuting patterns in the Willamette Valley using the Census Transportation Planning Package (CTPP)

The Oregon Department of Transportation (ODOT) recently completed a study of commuting in the Willamette Valley using data from the CTPP to help answer questions regarding the effects of commuting on transportation and growth management. Data was extracted from the CTPP database at three geographic scales to perform several analyses of commuter travel. County level data were used to provide a general description of commuting patterns. Data extracted at the minor civil division/place dataset were aggregated into travel analysis zones to evaluate commuter flows to major job centers and to evaluate commuter flows on 1-5, Data extracted from the place dataset were used to evaluate relationships between travel time, jobs to worker ratios, and levels of commuting. The CTPP proved to be a very useful tool for analyzing transportation and growth management issues related to commuting. This paper illustrates that even relatively simple analyses of data from the CTPP can provide valuable perspectives on the nature of intercity commuting in a region, its magnitude and its relationship to congestion, household location decisions and jobs/housing balance.