The purpose of this research is to conduct comparisons between LEHD and CTPP regarding trip productions, trip attractions and origin-destination flows at different levels of geography. The following case study has been completed.
Over the last several decades the increase in household vehicles and the number of jobs has outpaced the growth in population in the Chicago area. These two trends have increasingly added to the amount of congestion during the peak periods and have directly contributed to increasing travel times to work. This case study will explore some of the factors that have contributed to rather divergent short-term travel-time trends in the Chicago area. We will do this by using the LEHD (On the Map) data and in the process reflect on the utility of the LEHD data for commuting studies and, more generally, regional transportation planning.
Conduct an evaluation of the Longitudinal Employer-Household Dynamics (LEHD) Data for the Chicago region as an alternative (to CTPP) data source for transportation planning.
Obtain the LEHD data sets for the Chicago region and compare them with the corresponding CTPP data sets at different geographic levels. Demonstrate the utility of the new information through a series of case studies.
Expected Results or Products:
In the last five years (2000 – 2005) the travel times have increased dramatically in the fringe suburban counties as home buyers seek inexpensive homes sitting on large lots. In Will County, which has the highest home ownership rate among counties reported by the 2004 American Community Survey (ACS), travel times have increase by 7.2 percent (32.0 –34.3 minutes). McHenry County, number two on the ACS list in home ownership, increased by 6.8 percent. At the same time the travel times in Cook County (Chicago) dropped from 32.6 minutes to 31.9 minutes. Unlike in 2000 Cook County now has a lower travel time to work than Will and McHenry Counties. The decline in Cook County is intriguing and merits close scrutiny as does the relative changes between Cook and the outlying counties.
The case study finds that there is continued strength in jobs in Chicago and Cook County, attracting large number of suburban residents. Concurrently, the suburban housing market is attractive to many home buyers but it adds to their travel time to work. The emerging housing developments are not generally in close proximity to the increase in resident workers. We make this assessment using the LEHD data and find that used properly LEHD may be a useful source of data on the dynamics of commuting in large metropolitan areas such as Chicago.
NOTE: A report or paper from this research is not immediately available.
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