M25 J5-J7 speed test - latest info
Discussion
I managed to get the following info out of the press office of National Highways which may be useful for those using this section of the M25.
Although much of the traffic management typically associated with roadworks was fully removed on 28 March 2025 and the carriageways went back to four running lanes, but we’ve maintained a 50mph speed restrictions as a safety measure, whilst we carry out the testing of the new technology and upgraded Stopped Vehicle Detection (SVD) system.
Upgrading the stopped vehicle detection is a separate piece of work to building the new emergency areas: we've been delivering the projects side-by-side to minimise disruption. Where the 50mph speed limit remains in place after the other roadworks have been removed the new emergency areas are all open and available for use.
The testing work isn’t visible from the roadside. Perceptions might be that there isn’t any justifiable reason for reduced speeds being displayed, however this isn’t the case, and it’s needed until these tests are complete. We rigorously test our Stopped Vehicle Detection systems before they go live to ensure they meet our high-performance specification. This can only happen when there are no roadworks and when drivers are able to use all lanes of the motorway.
This includes:
• Recording the road layout in the SVD system (a process that can only be completed once roadworks have been removed)
• Training the radar that the SVD system is based on to reliably spot stopped vehicles and not create false alarms for reflections, signage, and other factors
Toward the end of this testing period, we check the system’s its real-life performance by using overnight closures to stop one of our site vehicles on the edge of the radar coverage area to make sure it’s detected, and its location is correctly reported to the National Highways Control room.
The testing of the SVD is being monitored 24/7 and final commissioning is needed to get the technology performing in line with our high specification for the system, enabling National Highways to close lanes, set signs and get help on the way as quickly as possible.
When we can remove the speed limit is determined by when the newly installed system is performing to our specification, rather than a strict timescale. Normal operations (variable mandatory speed limits up to the national speed limit) will be reinstated once the tests are complete. We expect this to be before the end of May 2025 but are working hard to improve on this.
We know that this is frustrating, but we would like to reassure you that we’ll remove the temporary speed limits as soon as the testing has been completed.
Please can I take this opportunity to thank you again for contacting us and again we apologise for any inconvenience these works may have had on you. You can find out more about our National Emergency Area Retrofit programme here: National emergency area retrofit - National Highways.
Although much of the traffic management typically associated with roadworks was fully removed on 28 March 2025 and the carriageways went back to four running lanes, but we’ve maintained a 50mph speed restrictions as a safety measure, whilst we carry out the testing of the new technology and upgraded Stopped Vehicle Detection (SVD) system.
Upgrading the stopped vehicle detection is a separate piece of work to building the new emergency areas: we've been delivering the projects side-by-side to minimise disruption. Where the 50mph speed limit remains in place after the other roadworks have been removed the new emergency areas are all open and available for use.
The testing work isn’t visible from the roadside. Perceptions might be that there isn’t any justifiable reason for reduced speeds being displayed, however this isn’t the case, and it’s needed until these tests are complete. We rigorously test our Stopped Vehicle Detection systems before they go live to ensure they meet our high-performance specification. This can only happen when there are no roadworks and when drivers are able to use all lanes of the motorway.
This includes:
• Recording the road layout in the SVD system (a process that can only be completed once roadworks have been removed)
• Training the radar that the SVD system is based on to reliably spot stopped vehicles and not create false alarms for reflections, signage, and other factors
Toward the end of this testing period, we check the system’s its real-life performance by using overnight closures to stop one of our site vehicles on the edge of the radar coverage area to make sure it’s detected, and its location is correctly reported to the National Highways Control room.
The testing of the SVD is being monitored 24/7 and final commissioning is needed to get the technology performing in line with our high specification for the system, enabling National Highways to close lanes, set signs and get help on the way as quickly as possible.
When we can remove the speed limit is determined by when the newly installed system is performing to our specification, rather than a strict timescale. Normal operations (variable mandatory speed limits up to the national speed limit) will be reinstated once the tests are complete. We expect this to be before the end of May 2025 but are working hard to improve on this.
We know that this is frustrating, but we would like to reassure you that we’ll remove the temporary speed limits as soon as the testing has been completed.
Please can I take this opportunity to thank you again for contacting us and again we apologise for any inconvenience these works may have had on you. You can find out more about our National Emergency Area Retrofit programme here: National emergency area retrofit - National Highways.
Just came on here to find out what the hell was going on.
We have been visiting relatives this weekend and having endured the "system test" on the northern section, we decided to come home to the south west using the south section. Oh, and guess what.
At least they should have the decency to replace "system testing ' with "revenue collection ".
We have been visiting relatives this weekend and having endured the "system test" on the northern section, we decided to come home to the south west using the south section. Oh, and guess what.
At least they should have the decency to replace "system testing ' with "revenue collection ".
I expect the Highways people will be pleased during their testing, when their radar correctly detects a stranded vehicle. They can then switch on their gantry signs to close the affected lane(s).
Do they even think about the inevitable flaw in the whole system?
From the moment a vehicle becomes stranded, possibly 500 following vehicles will have already passed the preceding gantry, oblivious that a warning has been announced. All of those drivers will obviously be unaware of the danger they are heading towards.
Here is a 27 mph collision - HGV hits stationary car.
I have noticed on motorways which do not have a 'hard shoulder', many motorists remain driving in lane 2.
I guess statistically, that a stranded vehicle is more likely to come to halt in lane 1, so to avoid driving in that lane might be a sensible safety precaution.
Jon39 said:
I have noticed on motorways which do not have a 'hard shoulder', many motorists remain driving in lane 2.
I guess statistically, that a stranded vehicle is more likely to come to halt in lane 1, so to avoid driving in that lane might be a sensible safety precaution.
like those morons need another excuse to not use the lanes correctly
TheDrownedApe said:
Jon39 said:
I have noticed on motorways which do not have a 'hard shoulder', many motorists remain driving in lane 2.
I guess statistically, that a stranded vehicle is more likely to come to halt in lane 1, so to avoid driving in that lane might be a sensible safety precaution.
like those morons need another excuse to not use the lanes correctly
After witnessing a stranded vehicle on a motorway with no hard shoulders, the panic sequence of events becomes clear, even to morons.
Picture a busy traffic day, you are driving in lane 1, say 60 mph.
Immediately ahead of you is an HGV which you are following at a safe distance, but your distance vision is of course obscured.
Out of your sight ahead, is a stranded vehicle, blocking lane 1. A very unusual situation, so you are not expect anything out of the ordinary and there have been no gantry warning signs.
The vehicles ahead of you might be able to swerve out into lane 2 (if there is space), but with restricted vision you won't be able to see that. Each vehicle ahead in turn, has less and less time to react, until eventually a driver has no time to react, then crash.
This could all be easily solved by having an empty lane to the left, perhaps on the shoulder. A 'hard' shoulder if you will, where broken-down vehicles were at least out of a live, running lane.
It's f
king backwards progress and having to develop complex systems that will never work properly just to fix a problem of their own making by turning the shoulder into a running lane. I know people who refuse to use motorways where the hard shoulder has been removed.
It's f
king backwards progress and having to develop complex systems that will never work properly just to fix a problem of their own making by turning the shoulder into a running lane. I know people who refuse to use motorways where the hard shoulder has been removed.Funk said:
This could all be easily solved by having an empty lane to the left, perhaps on the shoulder. A 'hard' shoulder if you will, where broken-down vehicles were at least out of a live, running lane.
It's fking backwards progress and having to develop complex systems that will never work properly just to fix a problem of their own making by turning the shoulder into a running lane. I know people who refuse to use motorways where the hard shoulder has been removed.
There was a programme on I think the BBC about them not so long ago and the dangers that they present. The main one of being stranded in a live lane and the time that it can sometimes take before the signs actual activate and warn people that there is a stranded vehicle ahead.It's f
king backwards progress and having to develop complex systems that will never work properly just to fix a problem of their own making by turning the shoulder into a running lane. I know people who refuse to use motorways where the hard shoulder has been removed.Gassing Station | Roads | Top of Page | What's New | My Stuff