Case Study: Analysing Clean Air Zone (CAZ) Data

Data science team dashboards are a “game-changer” in understanding air pollution in Bradford and driving data-informed policy decision-making.

The Bradford Clean Air Zone (CAZ) was launched in September 2022 with the primary aim of reducing noncompliant levels of air pollution in Bradford and improving the health of its citizens. The objective was to increase the number of CAZ-compliant vehicles, reduce pollutant levels, and decrease GP and hospital attendances for cardio-respiratory illnesses linked to poor air quality.

The HDRC Data Science team was tasked with analysing millions of records of vehicle data from CAZ traffic cameras, which were too complex for traditional tools like Excel. Using advanced analytical methods and data science tools, the team extracted and cleaned the data, employing the programming language 'R' to investigate patterns and detect noncompliant vehicles. They developed interactive dashboards to allow the Sustainability Team to examine vehicle types and CAZ compliance status by time and location.

The dashboards confirmed the hypothesis that Manchester Road had a high frequency of retrofitted buses contributing to poor air quality. This data-backed insight enabled the Sustainability Team to optimize CAZ compliance strategies and target interventions more effectively. The dashboards have been used to provide pollutant source data to the government’s Joint Air Quality Unit for statutory evaluation, influencing the duration of the CAZ and other interventions to improve air quality.

Sally Jones and Elizabeth Bates from the Sustainability Team plan to recruit an Environmental Analyst to build on the current data work. This analyst will develop further insights to inform policy and decisions. The HDRC Data Science Team will support this process by identifying high-quality candidates, providing peer-led data science support, and enabling access to data science tools. Case study: Analysing Clean Air Zone (CAZ) data. Elizabeth Bates and Sally Jones highlighted the invaluable help in transforming CAZ traffic camera data into a usable format, enabling intelligence-led decisions about vehicle upgrades and achieving air quality standards.

"The dashboards created by the HDRC team have been a gamechanger for us. They have revolutionized the way we view and utilize our data, enabling us to represent information more effectively and derive actionable insights with ease." - Elizabeth Bates, Monitoring and Evaluation Manager, Department of Place.

"The analysis conducted by the HDRC Data Science team has provided immense value to our department in terms of cost savings. By leveraging their expertise, we avoided the expense of hiring external consultants, saving between £25,000 and £30,000. This work has highlighted the importance of investing in data science skills within the council." - Sally Jones, Environment Manager, Department of Place, Environment Team.

Key takeaways

• The Bradford Clean Air Zone (CAZ) aims to reduce air pollution and improve health.
• The HDRC Data Science team used advanced data science tools to analyse complex data and develop interactive dashboards.
• The dashboards confirmed the hypothesis about retrofitted buses on Manchester Road.
• The dashboards provided robust insights for optimizing CAZ compliance strategies and targeting interventions.
• Collaboration between the HDRC Data Science team and the Sustainability Team has revolutionized air pollution analysis in Bradford, leading to significant cost savings and improved decision-making.