Traffic Volume Map Application Help

Please direct any questions or comments regarding this Help page, or the map itself, to Joe St. Charles at StCharj@WSDOT.WA.GOV or (360) 570-2381.


Navigating the Map

The map can be navigated using several methods. Tools are available for zooming, panning and other typical methods of web-map navigation. An address search is also available, as well as drop-down menus for zooming to a specific city or county.


Navigation Toolbar

Seven tools for navigating the map are available at the top of the screen (circled in the graphic below). The functionality of each is described below.

Screen shot 1
Zoom in icon Zoom In - Click on the icon to activate, then click on the map and hold while moving the mouse to define a rectangle, then release to zoom to that area. The smaller the rectangle defined, the greater the change in map scale will be.
Zoom out icon Zoom Out - Click on the icon to activate, then click on the map and hold while moving the mouse to define a rectangle, then release to zoom out from that area. The smaller the rectangle defined, the greater the change in map scale will be.
State view icon State View - Click on the icon to zoom out to full map view.
Prev view icon Prev View - Click on the icon to go back one step in the history of user-selected map views.
Next view icon Next View - Click on the icon to go forward one step in the history of user-selected map views.
Information icon Information - Click on the icon to activate, then click on a line or point representing available traffic data in order to display that data.
Pan icon Pan - Click on the icon to activate, then click and hold on the map to pan the map as the mouse is moved.

Map Quick Zoom

At the left side of the screen, under the Map Services heading, is the Map Quick Zoom pane. If the Map Quick Zoom pane is clicked on, Zoom to City and Zoom to County drop-down menus are displayed. Selecting a city or county from one of these menus will zoom the map to the chosen jurisdiction. You can also type a city name in to the drop-down menu.








Address Search

At the left side of the screen, under the Map Services heading, is the Address Search pane. If the Address Search tab is clicked on, Address, City and Zip Code text boxes are displayed. Enter a street address and city or zip code, then click on the Search for Address button are hit enter on your keyboard. The closest match in the software’s address database will be shown to the right of a red diamond. Clicking on the word “Center” below the address will center the map on this location. Clicking on the word “Zoom” will center the map on this location and then zoom to it. Similar addresses will be listed in blue below the words “did you mean”. Clicking on one of these will replace the closest match to the right of the red diamond.

If the software is unable to find any address match, the city or zip code will be listed to the right of the red diamond. The zoom and center functions will then operate in relation to the geographic center of the city or zip code.

Note that the search function may not work properly if both the directional indicator portion of an address (i.e., SW, NW, SE, and NE) and the street name suffix (e.g., Ave, Dr, St) are left out.


Map Layers

Three traffic volume datasets are available through the map. These are the Annual Traffic Report (ATR) Counts, Traffic Counts and Traffic Sections map layers. Tabs for each of these are provided under the Map Layers heading on the left side of the screen. Clicking on the tab for a given layer will display a legend showing how data from that layer is presented on the map. Clicking in the check box above the key (circled in red in the graphic) will toggle the display of that layer on and off.


Retrieving Data From the Map

Clicking on the circled “i” in the navigation toolbar at the top of the page activates the information tool. Once the tool is activated, the user can click on points along the state highway system to retrieve available traffic data for those locations. The data is provided in a table display at the bottom of the page that contains tabs that correspond to each of the three traffic data layers. Clicking on the word “Print” found at the bottom of each tab will create a printable version of the data contained in the active tab within the table.

Data Table Example:


The ATR Counts Dataset

The ATR Counts dataset provides the state highway Annual Average Daily Traffic (AADT) volumes published within WSDOT’s Annual Traffic Report (ATR). AADTs are only provided for locations where actual traffic counts have been conducted in one or more of the last four years. An asterisk placed to the right of an AADT signifies that it was derived from a traffic count conducted during the year the AADT is provided for (shown above the AADT). All other AADTs are estimates generated by applying annual traffic growth factors (calculated from WSDOT’s network of permanently installed traffic recorders) to traffic counts conducted in prior years.

The State Route Identification (SRID) field provides the WSDOT code for the roadway the count location is on. The Location field describes the count location in terms of the State Route Milepost and Ahead/Back Indicator of a nearby physical feature of the roadway (e.g., an intersection or bridge). Within this description, the words “before” and “after” are used in relation to the increasing direction of mileposting. (Detailed explanations of WSDOT’s route coding and mileposting conventions are provided in the appendices of this document.)

The Direction of Travel field indicates whether the AADTs reflect a single direction of travel (e.g., northbound, southbound, etc.) or both directions of travel combined. The AADTs will always represent bothways traffic unless the count location is on a section of roadway where traffic is carried in only one direction. However, regardless of the number of directions in which traffic is carried at the count location, within the map data is only plotted to the side of the roadway carrying traffic in the increasing direction of mileposting. This convention is only deviated from when the count location is on a section of roadway where traffic is only carried in the decreasing direction of mileposting (in which case the data is plotted to that direction of travel).

ATR Counts Dataset Example:


The Traffic Counts Dataset

This dataset is similar to the ATR Counts dataset, but differs in several ways. First, it only contains AADTs for a single year. Second, it does not include asterisks to indicate whether or not an AADT is based off an actual count conducted within the year the AADT is provided for. Third, while it contains all count locations found within the ATR Counts dataset, it contains additional locations as well.

There are two reasons the Traffic Counts dataset contains additional locations. The first reflects the fact that sometimes there are multiple traffic counting locations within WSDOT’s database that must logically carry the same traffic volume because there are no sources of access to or from the roadway between them. In this situation, only one of the locations will be listed in the Annual Traffic Report (and therefore the ATR Counts dataset). In contrast, the Traffic Counts dataset will contain them all. The second reason is that there are some count locations within WSDOT’s database where the best available data is accurate enough for some purposes, but does not meet the precision standards set for inclusion within the ATR. Unlike the ATR Counts dataset, the Traffic Counts dataset contains these locations.

The final way that the Traffic Counts dataset deviates from the ATR Counts dataset is that the former carries the percentage of total traffic in each of three truck categories when available. (A detailed overview of WSDOT’s vehicle classification scheme is provided in the appendices of this document.) Caution is advised when using these percentages. This is because most are derived from short duration traffic counts of three or fewer weekdays. The greater the variation in the percentage of the total traffic stream made up by different vehicle types during different days of the week or different seasons of the year, the more the figures provided will tend to be an inaccurate reflection of annual average truck percentages.

Traffic Counts Dataset Example:


The Traffic Sections Dataset

This dataset provides AADTs for segments of roadway. The AADTs and segment boundaries are software generated estimates produced using the Traffic Counts dataset and a WSDOT dataset of physical roadway features (such as intersection locations). The dataset is intended to allow for a general visualization of traffic volumes on the state highway system, not precise estimates of traffic volume at the individual segment level. Individuals using it for the latter purpose should only do so with discretion.

Traffic Sections Dataset Example: