Case Study:

Sacramento, California

Methodology

Level of Effort

The level of effort described here focuses on the application of MEPLAN, since the regional travel model analysis (SACMET96) is a straightforward application of standard MPO travel modeling tools. Total estimated staff time for the Sacramento MEPLAN analysis was seven to 14 person-months (PMs), including two to three person-months of MEPLAN staff time at the University of Calgary. The total cost for the analysis was roughly $50,000 for UC-Davis researchers and $20,000 for MEPLAN staff time. The analysis described here was a "quick and dirty" application; more extensive and thorough data and model development would add an additional level of effort.

The level of effort broken down by task was roughly as follows:

• Developing the network and zone structure for MEPLAN: about one PM. This can now be edited in ArcView, although it may be easier to have a person familiar with MEPLAN do it.

• Developing baseline data for MEPLAN: The cost depends on the state of the datasets at the MPO. It is helpful to have all of the various data described above, including land use, travel survey, and related data, for two base years. If all these data are available, the effort is a PM or two. The typical effort required in a large metropolitan region might be two to six PMs.

• Calibrating MEPLAN: one to two PMs by a MEPLAN staff person.

• Developing policy/scenario inputs: relatively easy, except to develop new networks for roads, bus, rail, etc. Complex scenarios might take one to two PMs of MEPLAN staff time, unless the MPO takes the time to learn how to edit the MEPLAN network.

• Running MEPLAN scenarios and processing output: one to two PMs for a few scenarios.

The MEPLAN application described here makes use of a high-quality travel model and good travel data. Desirable travel model features include auto ownership feeding elastic trip generation; elastic trip distribution, that is, iterated across all submodels to equilibrium; at least three time periods; a logit mode choice model; and bus, walk/bike, and rail modes, if applicable. If some or all of these features are not included, sensitivity to land use policies and feedback will be reduced. The Sacramento application did not include heavy trucks, however. If the MPO has a truck freight model, an additional two to three PMs would be required, but the ability to track freight movement and also to model commercial land uses would be greatly improved.

Land use data were developed by the researchers. High-quality land sales price data were the most difficult to obtain, and the large zones in MEPLAN also caused problems with averaging over a large ranges of data values. The above level-of-effort estimate is also with only a land model, not a floorspace model. A floorspace model is recommended to provide a check on land consumption and also to represent land use controls more accurately. Floorspace models also track building types by occupying activity, so that new activities must rehabilitate the building. This slows down turnover of activities and is more realistic. If floorspace data and lease payment data (by activity by district) are not readily available, this would add a significant data gathering or estimating effort, adding perhaps six to 12 PMs of effort.

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