FAQs

The Council is creating new and expanding existing 20 mph zones. This means reducing the speed of all roads within the zone to 20 mph, and introducing speed reduction measures such as speed humps, raised junction or crossing points, or ramps to slow vehicles down to make the zones self-enforcing. This will ensure vehicles remain within the speed limit in the zone and where traffic calming has not been installed the Council will monitor those roads and install any measures needed in the future.

The Council will be looking to install those speed reduction measures where speeds are showing above the enforcement threshold or will be likely to be above the enforcement threshold. 

The enforcement threshold is usually 10% over the prescribed speed limit plus 2 mph.

A self-enforced zone is where the traffic calming measures installed will engineer drivers to stay under the speed limit, rather than solely relying on enforcement through police or cameras.

Yes. The Royal Society for the Prevention of Accidents (RoSPA) has stated that if a pedestrian is hit by a vehicle travelling at 20 mph there is a 2.5% chance that they will be fatally injured, compared to a 20% chance at 30 mph.

Slower speeds will also reduce the chance of a collision occurring as people have more time to react, benefiting drivers too.

Yes. But just to clarify the Council cannot make roads such as the A12, A1400, and the A406 20 mph, as they belong to Transport for London. All roads within the designated plan will be reduced to 20 mph.

You will see signage placed on lamp columns or posts at the entry point to a 20 mph zone as well as road markings on the carriageway. The Council is also looking to install what it is known as repeater signs to remind drivers that they are in a 20 mph zone.

Transport for London states that Imperial College London's research into the impact of 20 mph speed limits suggests they have no net negative impact on exhaust emissions. Results indicated clear benefits to driving style and associated particulate emissions. The research found that vehicles moved more smoothly, with fewer accelerations and decelerations, than in 30 mph zones, reducing particulate emissions from tyre and brake wear.

It is unlikely that the lowering of speed limits to 20 mph will cause congestion. Overall journey times are impacted by delays at junctions rather than speeds.

Enforcement plays a crucial role in ensuring drivers comply with speed limits. However, it is impossible to enforce all roads at the same time, and installing speed cameras on all roads is not a cost-effective solution in reducing speeding.

The Council is submitting requests to Transport for London and Metropolitan Police for use of its Mobile Laser Cams that can be deployed quickly but self-enforced zones are a cost-effective and efficient way to reduce speeds and create a safe environment for all road users including drivers.

Yes, the Council will be officially amending the traffic order of roads to the new speed limit so these can be enforced by the Police.

No. Any income received from action by the Metropolitan Police is received by Central Government. At this time, the Council do not have the authority to take any income nor have the powers to enforce speed limits.