Traffic count

Transport Scotland collects traffic count data to help us monitor the traffic levels on our trunk roads.

All of the traffic count data is held in the Scottish Roads Traffic Database (SRTDb).

You can get traffic count information by :

• utilising the map application on this site
• making a specific request to us for traffic count information

We provide general traffic count data free of charge, although specific requests for traffic count data may incur a fee. 

Traffic data is collected from over 1,300 automatic traffic counter sites and over 50 weigh-in-motion sites located across the trunk road network.  We constantly monitor and review the location of the traffic counter and weigh-in-motion sites.
 
Depending on the traffic counter and its location, we collect traffic count data from the counters either manually on automatically using a telemetry connection to our control centre.  The data is then collated, validated and stored in the database.
 
Each weigh-in-motion site determines the weight of commercial goods vehicles, allowing us to collect a broad range of useful information in monitoring the use of trunk roads.

Where road improvement schemes permit or where a new trunk road scheme is constructed, we take the opportunity to install or upgrade the automatic traffic counters.

Once the data is processed, the outputs from the SRTDb’s include:

• Annual Average Daily Flows (AADF), this represents the average 24 hour traffic volume at a given location averaged over a full year
• Average Monthly Daily Flows, this represents the average 24 hour traffic volume at a given location averaged over a full month
• Daily Flows, this represents 24 hour count at any specified location
• 15 minute Flows
• Vehicle–by–Vehicle data, parameters stored on a vehicle-by-vehicle basis include lane, direction, class, speed and headway
• Congestion on Scottish Trunk Roads Reports.

The SRTDb can also be used to help us in:

• Monitoring day-to-day usage of the road network
• Estimating local traffic growth
• Planning for works
• Monitoring during works and events such as T in Park, The Open
• Asset Management / Evaluation
• Overweight Vehicle monitoring
• Before and After Studies.

The Department for Transport has an extensive database for traffic counts similar to that held by SRTDb for Great Britain.