About the Website

The TII Traffic Data website presents data collected from the TII traffic counters located on the National Road Network. The Website uses a dynamic mapping interface to allow the User to access data in a variety of report formats.

Map Interface

Green dots display the individual traffic counter locations around the country. Summary traffic data information can be obtained from each site by clicking on the green dot. On clicking a dot, a pop-up window will appear that summarises the traffic data and provides a link to more detailed data.

Site List

The traffic counter sites are also displayed in list format. The list can be accessed by clicking on the "List of Sites" button located above the map.

Search Function

The user may narrow their search for a particular site or sites by using the "search" function located above the map. By typing a key word such as a road number or a county name e.g. N2 or "Louth", the website will identify the counters on that road or within that county.

Site Data

The user may access a variety of traffic data reports by opening the "Site Data" link available in the summary pop-up window or in the List of Sites. The link provides the user with access to more detailed traffic data specific to the selected counter. This will allow the user to generate a number of predetermined reports for a selected date range using the calendar on the page. On the Calendar, green dates indicate available data. Clicking a date (or click, hold and drag across a range of dates) highlights the selected dates in yellow. The right hand panel indicates the dates selected and the reports available which are as follows: Summary: Displays the traffic data in summary format for each year.

Volume: Provides vehicle volume reports across the range of dates selected.

Class: Provides a breakdown of traffic volumes into vehicle classification volumes. Clicking on a particular report will download the given report (this may take a few moments). The user can further modify the report by using drop down menus under Channel, Time Period or Class. On the top left hand side of the reports page the user can press the various buttons to export the data into other formats such as Excel.

Explanation of Reports

Weekly Volume Report: This report shows vehicle flows for each daily interval (default interval is 1 hour) for every day of the specified week. If a number of weeks are chosen, the average hourly volume for each weekday is displayed. Weekly Summary Report: This report shows the workday and weekday average interval volumes for a given week. Monthly Volume Report: This report shows vehicle flows for each daily interval (default interval is 1 hour) for every day of the specified month. Monthly Summary Report: This report shows the workday and weekday average interval volumes for 12hr, 16hr and 24hr periods for a given month. This report also shows the AM and PM peak flows. AADT estimate: This figure is an estimate of the mean daily traffic volume over the course of a year. An exact computation of AADT involves dividing the total traffic volume in the year by the number of days in the year. The AADT is a measure of the total traffic over a road and thus is useful for pavement and base design. However, it fails to take account of seasonal, monthly, daily and hourly variations in traffic flow. Therefore it is not very useful for capacity design and a second parameter, the 30th Highest Hour, is needed. Coverage: This figure highlights the percentage period in a given year that data was collected from a particular site. Data is only available in 2013 from March onwards. HGV%: This figure indicates the percentage of heavy goods vehicles from recorded data. Articulated and Rigid Trucks are classified as HGVs. Buses and vehicles pulling trailers do not fall under this category.

Important Notice