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VMT Based on Percentage Increase-Decrease in Annual Traffic Counts 1982-2008

Status and Trend

Interpretation and Commentary

At or somewhat better than target
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Status: At or somewhat better than target
Trend: Rapid Improvement
Confidence: High

  • Vehicle Miles Traveled, the number of vehicle miles traveled in a typical summer day in the Lake Tahoe Basin, is a modeled number. The model takes into account traffic volumes and household and visitor travel data. Among other parameters, the model calculates from this data: a) average number of trips per person per day; b) average trip length; and c) average vehicle occupancy. These parameters are used as inputs to come up with VMT.
  • Since 1981, the TRPA has used a series of progressively more sophisticated models to estimate VMT. As the models improve and old software becomes obsolete, it is not always possible to update previous VMT estimates to be comparable with more recent estimates.
  • The VMT threshold established by the TRPA Regional Plan calls for a 10% reduction in VMT from 1981 values. The 1981 estimated VMT level was 1.65 million miles per day. A 10% decrease from this number equates to 1.48 million miles per day. Based on traffic counts collected by Caltrans and NDOT the most recent estimate is 1.42 million miles per day, a 14.2% reduction from 1981 values
  • The model is run with updated data every 5 years. The model is updated as new socio-economic data becomes available and is calibrated with traffic volumes collected by Caltrans and NDOT.




Traffic Volume Count Locations

Traffic Volume Count Locations

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Additional Info

Lake Tahoe Region 1982-2008 VMT Based on Percentage Increase-Decrease in Annual Traffic Counts

Additional Info

Last Updated on Tuesday, 13 November 2012 11:03