A number of residents in eastern Yeovil say that speed-reducing features installed last year are not working.
Residents are backed up by town councillor Tony Lock, who says the attempt to reduce speed in Rosebery Avenue and St Michael's Avenue has proved ineffective.
But the county council's highways department says damaged cars are proof the measures are working.
The speed-reducing programme was completed last year and financed by a government grant. The implementation followed an extensive consultation exercise and included pinch points and road humps.
A report prepared for town councillors stated: "Councillor Tony Lock has brought this matter to the attention of the chairman.
"The road humps are configured in such a way that buses and emergency vehicles can pass without their speed being impeded.
"It is suggested, however, that the humps are also capable of being driven across by private motor vehicles without the need to reduce speed.
"Observations have taken place and it is suggested that many drivers, of all age groups, do not slow down. It is considered that this situation presents a considerable road safety hazard."
The highways department admits there are a few problems, which are currently being addressed.
But the department also says it has received complaints of damaged vehicles, which is proof that the measures are effective.
A recent monitoring exercise was described as encouraging by the highways department, which also said that speed readings will be carried out before a safety audit is produced.
Town councillors resolved to invite a highway department representative to the next meeting of the Buildings and Civic Matters Committee for further discussions.