WHEN considering a 20mph speed scheme, councils must consider guidance from the Department for Transport.
There are two types of initiative: limits and zones.
A limit includes the use of speed and repeater signs alone but crucially, a zone approach requires suitable traffic calming measures, such as speed bumps, which results in average speeds lowering enough to not need active enforcement.
A DFT report considering the effect of a 20mph initiative in Portsmouth concluded speed limits reduced average speeds by less than zones, partly because limits are most effective where speeds are already low.
Zones should generally be implemented where traffic calming measures are required to bring down higher average speeds.
In Worthing, residents are being consulted on a limit scheme, with no plans to introduce further traffic calming measures.
But the current proposal includes many streets in which average speeds may be too high for a limit scheme alone to significantly reduce speeds.
A report to the CLC suggests around 17 streets may require traffic calming, at a cost of up to £1.2 million. The costs are not included in the budget set-aside for any potential 20mph initiative.
Is there any point in having 20mph limits?
AVERAGE speeds on nearly half of roads surveyed may be too high for a 20mph speed limit to be effective on its own.
The DFT states that introducing limits on roads with average speeds of 24mph or less is most likely to lead to a ‘general compliance’ with the new 20mph limit, as speeds are already low.
Of 142 roads surveyed in Worthing, 43 per cent had an average speed of over 24mph, while the rest conformed with the guidance.
‘20’s pointless’ argue the current drawings for the town’s limit scheme includes far too many of these ‘unsuitable’ roads and should be excluded from the proposals.
Elise Mason said: “The proposals being consulted on include far too many roads in which speeds are too high to bring speeds down to 20mph by using signs alone.
“We believe the scheme is doomed to fail without expensive and unnecessary traffic calming measures, for which there is no budget.
“Also to put in 20mph signs where speeds are already around 20mph is completely pointless.”
Government research suggests implementing a 20mph limit reduces average speeds by up to 2mph.
This is a key factor in determining the recommended 24mph cap.
So what is the point of introducing 20mph limits on roads where people are already driving at 20mph?
Duncan Kay said: “If average speeds are around 20mph most drivers obviously feel this is an appropriate speed, in fact some are driving slower.
“The problem is that others are driving faster, some much faster.
“Introducing a 20mph limit sends a clear message that the appropriate speed for minor residential roads is 20mph or lower.”
In response to criticism of the planned inclusion of some roads, West Sussex County Council principal engineer Richard Wells said: “There are some unsuitable roads on there but the criteria we were given was to create a borough-wide scheme.
“We could out take a road where speeds are above 24mph but potentially, you could throw out a whole neighbourhood. The scheme is liable to change, depending on the results of the consultation.”
Collisions in roads included in 20mph proposals
NO FATALITIES and just 34 serious injuries occurred on Worthing roads included in the current 20mph limit plans over a five-year period.
A drunk passenger getting his thumb caught in a taxi door and a mobility scooter hitting a shopper in a pedestrianised area were just two serious incidents recorded between 2008 and 2012.
The data, obtained from the Highways Agency, shows a range of contributory factors for the collisions, including motorists failing to look properly and a car being used as a weapon.
Opposition groups have clashed on the significance of the findings, with 20’s pointless Gavin Ross arguing the amount of accidents is ‘miniscule’.
But 20’s Plenty says this approach ignores the majority of collisions, which are judged as ‘slight’.
Mr Ross said: “In our view, we do not believe reducing the speed limit to 20mph will help avoid the majority of collisions.
“Looking at the list, we feel very few if any, would have been prevented or made less serious by a lower speed limit.
“Detailed data for slight accidents is not available and while they are not to be ignored, serious collisions cause the most pain and disruption.”
Duncan Kay interpreted the information differently.
He said: “Six of the incidents clearly would not have benefited from slower speeds and two might not have. In the other 16, if people had been going a bit slower then the collision would either have been avoided or would probably have resulted in less serious consequences.
“The leading cause of road collisions as recorded by police is ‘failed to look properly’.
“But the point is that when someone fails to look properly and pulls out, the vehicle they didn’t see would have a better chance of reacting and stopping in time if it was going a bit slower.”
What do the police say?
THE whole point of 20mph limits is to be ‘self-enforcing’, the Department for Transport states.
In its 2013 guidance, the department says: “To achieve compliance there should be no expectation on the police to provide additional enforcement beyond their routine activity, unless this has been explicitly agreed.”
Sussex Police does not expect to commit extra resources to policing the proposed new limits.
A spokesman said: “While Sussex Police is able to enforce any legally established speed limit, we do not routinely expect to enforce 20mph limits because as part of the consultation in the implementation of the 20mph limit, the new area should comply with the Department for Transport guidelines for self enforcing schemes.
“However, where drivers are exceeding the speed limit through wilful offending, officers can enforce the limit and prosecute offenders.”
Duncan Kay said that it is ‘essential’ to have community support.
He said: “DFT is absolutely right. It is essential to have community involvement. Really this should be led by the local highways authority as they have a statutory duty to ensure the safety of all road users.”
20’s Plenty constantly claim the scheme has 60-70 per cent of support of residents.
A recent Herald poll, however, revealed 87 per cent of readers who voted were against the plans.