Southwest Environmental Limited

Automatic Traffic Counts (ATC): Data for Planning & Highways

Automatic Traffic Counts (ATC) provide a cost-effective method for gathering high-quality, long-term vehicular data. Unlike manual counts, ATC surveys operate 24 hours a day, typically over a 7-day period, capturing essential metrics for volume, speed, and vehicle classification. This data is critical for supporting Traffic Impact Assessments and validating highway design parameters.

Survey Methodologies

We utilize industry-standard equipment to ensure data accuracy and reliability, tailored to the specific environment of the survey location.

• Pneumatic Tubes: A common and highly accurate method for measuring axle strikes to determine volume, speed, and classification (short-term surveys).
• Radar Units: Non-intrusive sensors used for high-speed roads or areas where road surface installations are not feasible.
• Pedestrian & Cycle Monitoring: Specialized counters to support bicycle and cycling consultancy and sustainable travel planning.

Why are ATC Surveys Required?

In the context of a planning application, Local Highway Authorities often require baseline traffic data to assess the safety and capacity of a proposed site access. ATC data provides the 85th percentile speeds required to determine Visibility Splay requirements and helps quantify the environmental impact in terms of noise impact and air quality.

Technical Authority

Our traffic data services are integrated into our broader Environmental Impact Assessment (EIA) workflows. By combining ATC data with our expertise in Travel Plans, we help developers demonstrate that their projects are sustainable and compliant with NPPF requirements. With over 900 projects delivered, SWEL provides the technical evidence needed to satisfy rigorous highways audits across the UK.