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Inconsistent use of Smart gantry signage & congestion

Reported via desktop in the Sign issue category anonymously at 08:30, Wednesday 17 March 2021

Sent to National Highways less than a minute later

Over the last few weeks the Smart gantry signage on the approach to J19 of the M4 approaching the M32 eastbound, does not appear to be utilised to its potential and is very congested... My question, why are you not allowing use of the left hand lane to ease this congestion and why is their use so inconsistent? Regards, Rob L

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  • Thank you for contacting Highways England. concerning the use of the Smart gantries.

    We shall look into this issue and aim to provide a response by 31/03/21.

    Can we please ask that you check back on this date for an update.

    Kind regards

    Highways England

    Posted by National Highways at 14:30, Wednesday 17 March 2021

  • Thank you for your report about our Smart gantry signage on the approach to J19 of the M4. We appreciate you taking the time to bring your concerns to our attention.

    The decision to open / close a lane is a human one, lockdown has made traffic patterns less predictable and so much of the previous data we had about opening and closing the hard shoulder is not currently useable. There are at time technical issues that may limit our ability to open the carriageway. With safety as our number 1 priority, we’ll not open the smart motorways unless it is safe to do so. As traffic levels are increasing now that lockdown restrictions are starting to ease, issues are now coming to light that need to be fixed. Our smart motorways use a systems called MIDAS (Motorway Incident Detection and Automatic Signalling) which uses sensors in the road to monitor traffic speed and volume. This is designed to automatically set signs and signals based on current conditions. When the decision is made to open or close a hard shoulder on a smart motorway section, this has to be done by an operator. This has to be done one section at a time, so will be prioritised depending on requirements. When this happens, the effect of doing this downstream has to be taken into account. We are working to improve our automatic systems and how we operate the smart motorway all the time. There have been times where we have not opened it when it would have been beneficial, due to a technical fault for example, and this has caused delays, so we know that when operating, it does bring benefits to customers.

    Without giving a specific example of a time, we are unable to give a more detailed explanation than this.

    We hope this answers your enquiry. If you have any further queries, please contact our Customer Contact Centre on 0300 123 5000 or Kind Regards Highways England

    Posted by National Highways at 14:38, Wednesday 31 March 2021

  • State changed to: Fixed

    Updated by National Highways at 14:38, Wednesday 31 March 2021

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