Drivers in south west London are the first in England to face being fined by a local council for speeding.
An eight-month pilot scheme run by Wandsworth Council will allow the body to fine motorists £130, but not add points to their licences.
Wimbledon Park Road and Priory Lane will be subject to the new rules.
Speeding offences are usually enforced by the Met Police but officers tend to concentrate on main roads and dual carriageways.
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The council is now stepping in after examining complaints from locals about drivers going too fast in residential areas, according to the Local Democracy Reporting Service (LDRS).
Recent studies indicate a quarter of vehicles broke the limit in Priory Lane while in Wimbledon Park it was one in five.
Drivers breaking the speed limit will be caught on camera and, for the first few weeks of the scheme, will be sent warning letters. After the initial period, fines will be applied, with discounts for early payments.
The council said it would use cash from the fines to fund road safety schemes in the borough.
If successful, the policy could be rolled out across London.
Copyright: BBC News