DETECTORS
ABOUT THIS PAGE
Loop detectors provide volume count, speed, and other data that make up the border wait time systems. This section of the data allows users to gather lane and detector-specific data.
WHEN TO USE DETECTOR DATA
Detector-level data are best when performing any analysis that is at a lane-by-lane comparison. They also provide more information about the flow of traffic as volumes can be collected at various points along a route to determine where traffic joins or exits a roadway. Lastly, detector data are useful to compare to crossing data to check for accuracy.
MAP PAGE
The primary detector page shows a map of all the detectors in the Cascade Gateway border crossing network. Users may zoom in and use the hand icon to move around the map to choose a different location. Loops are color-coded based on the primary mode of the lane they are located in.
Hovering over a loop detector on the map will show the loop's name. Clicking on the loop detector will bring up that specific loop page.
TO SELECT MULTIPLE LOOP DETECTORS TO LOOK AT
The primary view of the detector section examines one loop detector at a time. To look at data for multiple loop detectors simultaneously, right-click on each loop as selected. This will make a list on the left of the screen. Once the list is complete, click "Create Query" and this will open a Custom Query with those detectors pre-populated into the query tool.
INDIVIDUAL LOOP DETECTOR PAGE
Each loop detector has its own calendar view. Choose to view the data a year, month, or day at a time. Once the data is visible in the calendar view, clicking on an individual month will drill down to a day, and from that day to a table with data broken out by five-minute increment.
Data available include:
Volume -- the total number of vehicles entering the port-of-entry
Occupancy -- Percentage of time when the detector was occupied with a vehicle
Speed -- The average speed of vehicles over the detector in kilometers per hour. Detectors closer to the border will have less useful speeds since the queue tends to extend over them.
Vehicle Length -- An average length of vehicles crossing the detector in meters. This may be approximated for some detectors.
CHANGING A DETECTOR
After a detector is chosen by the map view and selected, users may still choose another detector by using the drop-down arrow to select a different detector. However they will need to be familiar with the naming conventions of the detectors to find the one they are interested in.
SELECTING A YEAR, MONTH, OR DAY
Year: Data go back to fall of 2007.
Month: Select a month to see a calendar view of that month. OR simply choose “Select” to see the full year of data for that year.
Day: Select a day to see the five-minute increment view of the day. OR simply leave it on “Select” to see the full month data.
SELECTING DATA POINTS
Place a checkmark next to each data element to be viewed on the calendar. They will be shown simultaneously.
DATA AVAILABILITY
The system receives 288 packets of data every day from partner agencies – one for every five-minute increment. If less than 80 percent of those packets are received, the color block is changed from green to yellow (50 – 80% of packets received) or red (0-50% of packets received). We recommend filtering out any days that do not have green availability tags if planning to use the data for analyses.
