A builder has forced a council to alter the height of its speed humps because they flout traffic laws. Patrick Cawley, 43, measured a flat-top road hump at 160mm - 60mm above the legal maximum height.
It will cost Camden council in north London tens of thousands of pounds to correct the humps in West Hampstead.
Mr Cawley, of West Hampstead, said: "The council's got to act fast.
"Some humps are intolerable and are severe even at low speeds. When I first complained, the council told me it was no worse than going over a pothole. That is ridiculous."
The Department for Transport confirmed that the humps were too high. A spokesman said yesterday: "The legal limit for road humps is a maximum of 100mm."
Mr Cawley met Camden transport engineers at one hump and they agreed that it would have to be modified.
The setback could affect humps throughout Camden and the whole of London.The council has already said it will have to lower humps in Westbere Road where Mr Cawley has measured them at 240mm.
A Camden council spokeswoman said: "We will be bringing the humps down to 100mm. Subsidence on either side of the road is to blame for the humps being too high. The cost of the modifications has not been worked out yet." Speed humps cost up to £25,000 to install. A six-week programme of work will begin in late August to bring the humps into line with regulations laid out in the Highways (Road Humps) Regulations 1996.
Brian Coleman, the former environmental chief at Barnet council who started ripping out all speed humps in the borough, said: "If Camden spent all the tens of thousands of pounds they waste on road-widening, traffic-calming and other unnecessary anti-motorist measures on resurfacing the roads it would be far more efficient.
"The most upsetting thing is the way Camden's road safety team treat as of no importance the frail, the elderly and the handicapped. I am not against road safety but most of the work they are doing is illegal."