A traffic engineer is a specialist who models, analyses and interprets traffic data to assess the performance of road junctions and networks. Traffic engineers support transport planners on planning applications by carrying out the technical junction capacity assessments, traffic modelling and network impact analyses required to demonstrate that a development's traffic impact is acceptable. They use specialist software - ARCADY for roundabouts, LINSIG for signal-controlled junctions and VISSIM for more complex microscopic simulations - to test junction performance under current and future conditions.
What they do
- Commission and manage traffic surveys at key junctions and screenlines
- Carry out junction capacity assessments using ARCADY, PICADY and LINSIG
- Develop strategic traffic models to assess network-wide impacts
- Carry out microsimulation modelling using VISSIM and AIMSUN
- Design signal timings and optimise junction performance
- Prepare parking stress surveys and parking needs assessments
- Advise on controlled parking zone design and Traffic Regulation Orders
- Assess pedestrian and cycling flows and safety at junctions
When you need one
A traffic engineer is needed when planning applications require technical junction capacity assessments, traffic modelling or when significant network impacts need to be demonstrated.
Typical costs (UK, 2025)
| Job type | Typical cost |
|---|---|
| Traffic survey (per count point) | £200 - £500 |
| Junction capacity assessment | £800 - £2,500 |
| Traffic modelling (VISSIM or ARCADY) | £1,500 - £5,000+ |
| Transport model calibration | £3,000 - £10,000+ |
| TRO preparation | £500 - £1,500 |
| Parking stress survey | £600 - £1,500 |
| Hourly rate | £75 - £140 / hr |
Traffic modelling costs depend on the complexity and scale of the model. Large strategic models covering a wide network area can cost significantly more than simple single-junction assessments.
Qualifications to look for
MCIHT is the standard chartered qualification for traffic engineers. Required by most highway authorities for junction capacity assessments submitted with transport assessments.
TPS membership complements MCIHT for traffic engineers with a transport planning focus. The Transport Planning Professional (TPP) qualification demonstrates specialist competence in traffic analysis and modelling.
How to find a traffic engineer
Frequently asked questions
What is ARCADY?
ARCADY (Autos-Research Capacity and Delay at Roundabouts) is a software tool used by traffic engineers to assess the capacity and performance of roundabout junctions. It is widely used in transport assessments to demonstrate that a development's traffic impact can be accommodated within acceptable performance parameters. The local highway authority will typically specify which software tools are acceptable for junction capacity assessments.
What is a traffic count?
A survey of vehicle movements at a point on the road network. Manual classified counts (by observers), pneumatic tube counts and automatic traffic counters are all used depending on the level of detail and duration required. Traffic counts are used to calibrate traffic models, establish baseline conditions and assess the proportion of different vehicle types using a road.
What is a junction capacity assessment?
An analysis using traffic engineering software - ARCADY for roundabouts, LINSIG for signal-controlled junctions, PICADY for priority junctions - that tests whether a junction can operate within acceptable performance parameters given additional traffic from a development. The assessment must demonstrate that queue lengths and delays remain within the highway authority's acceptable limits.