The background

In the summer of 2019, a network of smart traffic sensors were installed in Cambridge to monitor the impact of the Mill Road bridge closure. A high concentration of sensors were installed for approximately 18 months to gather data before the closure, during the time when there was no vehicle traffic coming over Mill Road Bridge and then after the bridge re-opened.

Due to the success of the sensors and the level of insight it is possible to  gain, additional sensors have since been installed in more locations across the city and the network is expected to continue growing.

Data for the more permanent traffic sensor sites, outside of the Mill Road project sensors, are published on this page.

The data

The data below provides traffic counts at one-hourly intervals, broken down into 8 vehicle categories. Data is provided from the installation of the sensor up to 09/05/2022. We aim to update this dataset on a quarterly basis.

The 8 vehicle categories are: 'Car', 'Pedestrian', 'Cyclist', 'Motorbike', 'Bus', 'OGV1', 'OGV2' and 'LGV'.

The counts are broken down into inbound (In) and outbound (Out) journeys. Please see the 'Location List' below to establish which compass directions the 'In' and 'Out' are refering to for each sensor, as it differs by location.

Some sensors record counts across three 'count-lines' which enables the sensor to provide more accurate counts at different points across the road and is particularly useful for picking up pedestrians. Sensors with multiple count lines split the count-line into: the centre line, a left-hand side line (LHS) and a right-hand side line (RHS). For sensors containing more than one countline, the data below is disaggreageted by the individual countlines. For sensor-level counts, simply aggregate the centre, LHS and RHS count-lines together.

Please note that at some locations the sensor number has changed (e.g. the Perne Road sensor used to be Sensor 16 and is now Sensor 44). Please refer to the 'Location List' which details the current and previous sensor numbers of every locations.