Traffic Data Program

Legacy: 1997 2015 Annual Statistics

The Ministry of Transportation compiles traffic data statistics each year at specific spot throughout the province. Summary statistics such as AADT (Average Annual Daily Traffic); SADT (Summer Average Daily Traffic); AAWDT (Annual Average Weekday Traffic); AAWET (Annual Average Weekend Traffic) are presented along with the specific data collected at each site for each year presented.

Be aware that the following downloadable files are all in ZIP format, and are very large

Accuracy

Traffic data is obtained by automated counting equipment which is subject to hazards. Data from these devices are carefully screened and adjusted to compensate for these infrequent events. Most of the count sites use induction loops to count the traffic volumes. A small percentage of special sites are counted using pneumatic hose. The accuracy of the data is subject to the precision of the data collection methodologies and the statistical and theoretical strategies used in the projection of short count data sites into annual statistics. The Ministry intends to make 2004 and later traffic volume data available through a separate website which is under development. There will be a significant difference in that the 2004 and later data from short count stations will be linked to the appropriate permanent count stations using the "factoring" methodology whereas the pre-2004 data was linked by a 'best-fit' regression analysis. Users of traffic volume data must be aware that as a result, caution is to be used in analyzing time series data which spans the Jan. 1 2003 "boundary".

Statistical Preparation

nformation is derived from data collected in 15 minute intervals for the entire year (at permanent count sites) or typically 8 days (at short count sites). The data from permanent count sites form the statistical basis upon which the SADT's are derived. SADT's from the short count sites are created by comparing the pattern of data for each short count site to the most similar permanent count site. The information produced is presented as an estimated average daily traffic volume for the months of July and August.

Composite Counts

Where two or more sites are physically located close to each other, data may be aggregated to form a 'composite count'. In the simplest case, an SADT for two converging ramps at an interchange may be added to produce an SADT for the ramp after the convergence. In the most complex case, the raw data of two or more different locations are added and / or subtracted to produce a new data set for a location at which no actual count was taken.

Highway Direction and Count Site Location

For simplicity, MoT assumes that highways in British Columbia are described to be north-south or east-west. The major exception to this rule is Route 1 on Vancouver Island, in Vancouver and in the Fraser River Canyon where the primary direction is changed from east-west to north-south. Exceptions also occur on Route 99 and Route 6. Descriptions of count site locations are typically stated using direction and distance from a cross road, municipality, bridge or other landmark. The direction of the count locations from these landmarks will be in terms of the predominant direction of the entire highway route and may not reflect the true compass orientation of the highway at that location.