Speed and Weight Limit Enforcement - Tower Bridge

  • Published: Speed Check Services, no date
  • Authors: Speed Check Services
  • Date Added: 18 Mar 2013
  • Last Update: 18 Mar 2013
  • Format: pdf


To the address Transport for London’s problem of high numbers of vehicles travelling at excess speed across Tower bridge as well as large numbers of overweight goods vehicles using the crossing.


SPECS average speed enforcement cameras were used to measure speeds across the bridge. A weight system was used to identify vehicles in excess of the weight limit (18t), with those violating the limit captured on ANPR for additional verification.

Key Findings:

  • Induction loop and piezo-electric sensors in the road surface measure the length, number of axles, axle spacing and chassis height of each vehicle.

  • The data is collected by classification unit. The classification equipment is used to trigger ANPR and context image cameras which record a sequence of frames to provide proof-of-presence of overweight vehicles.

  • Vehicle classification data and images are written to disk and processed in a similar way to the speed violations using unique software developed by SCS.

  • Transport for London verify the plated weight of each vehicle and, if found to be in breach of the weight limit, a penalty notice is issued to the driver.

  • The number of overweight vehicles crossing the bridge has reduced considerably and the damage to the roadside furniture caused by RTIs has almost disappeared.

  • The number of overweight vehicles crossing the bridge has fallen from 6 per hour to 6 per day.


Speed reduction, Overweight vehicles,


Demonstrates that ANPR can be used successfully for monitoring overweight vehicles.