A group of volunteers in Wiltshire has caught 1,000 lorries in seven months ignoring weight restrictions on a 14th Century bridge.
Lorry Watch, in Bradford on Avon, is now calling for a more permanent way of monitoring traffic on the Town Bridge, which has an 18 tonne weight limit.
Possible permanent solutions to the problem will be discussed at a meeting of Wiltshire Council on Wednesday.
The council said it would improve signage in the area.
Lorry Watch was set up by residents who were fed up of vehicles exceeding the weight limit on the bridge which takes the A363 over the River Avon.
Clogs centre up
About 60 volunteers have been taking turns to stand by the side of the bridge from about 07:00 until 19:00 daily. If a vehicle has three or more axles it is over the limit.
They then note the registration plate which gets sent to the town council, which contacts the company that owns the lorry and gives them an official warning.
Repeat offenders can face a £1,000 fine.
Co-ordinator Stephanie Rideout said: "It just proves how many lorries are going over and causing problems in the town, so it's time to address it permanently and try and get the numbers down a lot more.
"It's the pollution, the hold-up of the lorries, it just clogs the whole centre up and it stops people wanting to stay longer in the town."
Bradford on Avon mayor John Potter said signs in the town were being upgraded to make it clearer to lorry drivers they could face prosecution.