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The M4 motorway – variable speed limits around Newport J24 to J28

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From today, Monday the 26th September 2016, the variable speed limit surrounding Newport along the M4 will be used to prosecute motorists. It is anticipated that an ‘advisory notice’ will be sent to drivers during the first 14 days and thereafter prosecutions will start for speeding offences. This brief note is designed to help motorists who regularly use this stretch of the M4 through Newport.

The variable speed limits along this part of the M4, are calculated by the amount of traffic between junction 24 for Coldra and junction 28 at Tredegar Park. The speed limit is likely to vary between 40mph and 70 mph. Drivers who use the stretch of road have concerns regarding the new enforcement action. As a result, Go Safe – the partnership that decides who should be prosecuted for exceeding the speed limit – have published answers to some of the most frequently asked questions. Below are some of the answers:

How does the variable speed limit scheme work?

Through this section of motorway, the mandatory speed limit is adjusted according to traffic conditions to keep vehicles moving at a steady rate. Normally during periods of no congestion on an incident-free carriageway, no variable speed limit signs or signals are set and the national speed limit applies. At busy times or in the event of an incident, sensors will detect congestion beginning to build up. The system calculates the optimum speed limit for the current amount of traffic and this is displayed on the electronic signals above lanes or at the side of the road.

Drivers may not be able to see why the signals are set; however, the system is detecting congestion building up and is using the speed limit signals to slow the traffic and keep it moving. Vehicles travel at more constant and similar speeds, making the journey smoother and safer for all. Congestion and queueing is reduced which in turn reduces a key risk of collisions from vehicles approaching the backs of queues. When the traffic flow has subsided and the signs and signals are no longer required, these will return to blank and the carriageway will return to normal motorway operation.

How is speed enforcement carried out in the variable speed limit?

Speed enforcement cameras are fitted onto overhead gantries. The cameras are activated when they detect a vehicle travelling in excess of the speed limit in force at the time.
The system has the necessary Home Office Type Approval (HOTA) which allows its use for enforcement purposes.

Who owns and operates the speed cameras?

Speed enforcement through the use of roadside cameras across Wales is managed and coordinated by GoSafe, a multi-agency partnership comprising all highway authorities within Wales and the four Welsh police forces. Within that partnership structure the Welsh Government owns and installs the cameras located on the M4 Motorway and the police, as the enforcement authority, are responsible for operating them and carrying out enforcement on a day-to-day basis.

What happens if there is a technical fault with the system?

There are built-in safeguards which prevent the camera from activating if there is a technical fault. The system is designed to ensure that it will only capture an offence when the equipment is working correctly. This is a requirement of HOTA.

I do not believe I was travelling in the M4 variable speed limit section at the time stated on my speeding notice sent by the police.

The speed enforcement system includes a calibrated, fully synchronised clock which meets required specific Home Office standards. Enforcement of the speed limit is carried out by the police and the processing of those offences is undertaken by the Central Ticket Office within South Wales Police. Any enquiries about specific speeding offences should be referred to the Central Ticket Office.

The speed limit changed just as I passed under the electronic sign, so I had no time to reduce my speed?

When a mandatory speed limit changes on the overhead signal, there is an automatic delay before enforcement can begin against the newly displayed limit.

Why does the speed limit sometimes change several times over a short stretch of road?

When an incident occurs, control centre operators may set signs and signals to protect the areas affected but the resulting slower-moving traffic can in some cases trigger an automatic setting to prevent queuing. The combination of these two setting modes can cause a combination of speed limits to be set in relation to the incident and the live traffic conditions.

This is normal operation, which ensures that the system protects road users from the effects of both the incident and the traffic congestion. On the westbound carriageway, due to damage sustained during the Brynglas tunnel fire in 2011, reduced lighting is in operation which requires the permanent display of a 50MPH speed limit on the approach and travel through the tunnel.
Works are currently underway at Brynglas tunnels to replace the lighting. These works are mainly taking place overnight to avoid congestion.

As with any prosecution for a speeding or motoring offence, there are various procedures that the police and the prosecution must follow before a fine or penalty points can be imposed.

If you have any legal questions concerning a speeding offence arising from the new variable speed limit imposed along the M4 around Newport or if you at risk of losing your driving licence, call 1 Motoring Solicitors for an initial fixed fee consultation.