About 40 billion kilometres a year are travelled on the nation's local roads and state highways. State Highway 1 in central Auckland is the busiest road in New Zealand, carrying more than 200,000 vehicles every day. Knowing about the number of vehicles using our roads enables us to plan more effectively. For this reason, we operate a comprehensive 'traffic counting' programme that gathers information on traffic growth trends and the types of vehicle using the state highways.
Reports on traffic data
- State highway traffic volumes reports(monthly)
(monthly) - Graphs of state highway monthly average daily traffic (MADT) percentage changes
- Historic state highway traffic volumes (annual)
Historic state highway traffic volumes (annual)
Contact us for more information on telemetry sites and general traffic monitoring.
How we count the traffic
We collect information on traffic growth trends and the types of vehicle using the state highways with the help of equipment that ranges in sophistication from weigh-in-motion and vehicle classification sites (with data collected continuously using telemetry) to simple portable pneumatic tube traffic counters. Through these methods, we produce:
- an annual summary of the actual counted or estimated traffic volumes for the entire state highway network
- monthly snapshots of trends at key sites.
Collecting the data
We collect data continuously at national telemetry sites using:
- bending plates scales (at four sites) to measure axle loadings
- dual inductive loops (at 79 sites) to classify vehicles by length
- Piezo electric axle classifiers (at one site) to classify vehicles by axle.
We also randomly collect data using:
- dual inductive loops (at 356 sites) to classify vehicles by length
- single inductive loops (at 707 sites) to count vehicles
- pneumatic tubes (at 313 sites) to classify vehicles by axle
- virtual counters (at 259 sites), which calculate information from adjacent sites.
Read the Traffic monitoring for state highways manual
Tell us your thoughts
We'd like your feedback on our data collection resources. Email us with your comments.