Emergency turning point?

[Big L]

Are contraflows, particularly on motorways, still a thing? I've seen a lot of motorways have fairly permanent looking concrete barriers installed, and for work either use lane closures or full carraigeway closures and diversions. Seemed more of a thing in the 80s-90s?

Contraflows are fairly routine on the M90 in my experience. Maybe they are generally less necessary on D3Ms.

You only need a contraflow on a D2M if there's work in the nearside lane needs doing. Either that or, less ideal, a full closure. It's possible to do overnight or weekend closures if the work is fairly simple and can be quickly completed, even if in sections. Typically that means resurfacing.

On a D3M or more, narrow lanes is more common nowadays than contraflows. This has been the case for at least the last decade or more.

I honestly can't recall the last contraflow I designed, it was so long ago. There's nothing difficult to designing them, you just need to find crossover points in locations nearish to the works area, (and 200-300m clear of any slip road), where the level difference is close to zero. With the presence of concrete barrier these days, that's not as easy as it was with steel barrier.

Lots of the managed / smart / digital works between M6 J13-16 was done with contraflows.

[Conekicker]

Contraflows are fairly routine on the M90 in my experience. Maybe they are generally less necessary on D3Ms.

You only need a contraflow on a D2M if there's work in the nearside lane needs doing. Either that or, less ideal, a full closure. It's possible to do overnight or weekend closures if the work is fairly simple and can be quickly completed, even if in sections. Typically that means resurfacing.

On a D3M or more, narrow lanes is more common nowadays than contraflows. This has been the case for at least the last decade or more.

I honestly can't recall the last contraflow I designed, it was so long ago. There's nothing difficult to designing them, you just need to find crossover points in locations nearish to the works area, (and 200-300m clear of any slip road), where the level difference is close to zero. With the presence of concrete barrier these days, that's not as easy as it was with steel barrier.

Lots of the managed / smart / digital works between M6 J13-16 was done with contraflows.

They must have decided they needed some extra width to get works vehicles through site, congestion on site can be a problem.

[traffic-light-man]

M62 J10-J12 and M56 J6-J8 used contraflow as well at times, but the M6 J21A-J26 works are seemingly just using the narrow lanes arrangement that Conecicker mentions.

[traffic-light-man]

Not quite in the same vein as the OP, but I thought still worth mentioning...

I noticed these 'three, two, one' marker posts on the M6 yesterday and thought they looked a little bit old fashioned, like the old ECP markers. I initially thought they were marking the ERA, but noticed it wasn't replicated at others downstream.

Low and behold, after some Street View investigation, it appears as though a section of the centre barrier is actually removable, presumably they have the equipment on handish to whip these out in an emergency.

I think I was aware of metal sections which always looked removable (I've always assumed they were ECPs, anyway), but these ones just blended in and I didn't even notice them.

[Conekicker]

Not quite in the same vein as the OP, but I thought still worth mentioning...

I noticed these 'three, two, one' marker posts on the M6 yesterday and thought they looked a little bit old fashioned, like the old ECP markers. I initially thought they were marking the ERA, but noticed it wasn't replicated at others downstream.

Low and behold, after some Street View investigation, it appears as though a section of the centre barrier is actually removable, presumably they have the equipment on handish to whip these out in an emergency.

I think I was aware of metal sections which always looked removable (I've always assumed they were ECPs, anyway), but these ones just blended in and I didn't even notice them.

The posts are indeed markers to an ECP, Type 3 posts as shown here https://www.standardsforhighways.co.uk/ ... series.pdf

Originally, when ECPs were actual gaps in the central reserve fencing, (with or without traffic cylinders), there would also have been posts in the central reserve, Type 5 or more likely Type 9 on the approach. The idea being that if the emergency services were looking to access an incident on the opposite carriageway, these posts would highlight the presence of an ECP ahead and the emergency vehicle could slow down to negotiate the ECP safely. Particularly useful at night on an unlit motorway.

In this particular case, it looks like there still is an openable crossover. The Type 5/9 posts are no longer present but the Type 3s are. They serve to inform a crew approaching the crossover point of it's presence ahead. Although if the crossover did need to be opened in an emergency the crew would be made aware of it's location before they set off from the depot.

[jnty]

How would you go about opening a crossover like that? The concrete sections look like they'd be pretty heavy!

[Conekicker]

How would you go about opening a crossover like that? The concrete sections look like they'd be pretty heavy!

I'm not familiar with that particular type of barrier but I'd guess that behind those plates are some wheels that can be wound down to facilitate moving the barrier. Whatever the actual mechanism is, it's unlikely to be a case of someone arriving on site and the crossover being open 5 minutes later. I suspect something nearer to 30 minutes would be a probable time period, providing everything is in working order.

You'd need to get some coning out on the opposite carriageway to control traffic that is approaching on the unobstructed carriageway as a bare minimum, to give the traffic you are U-turning room to move in.

ETM426.pdf

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ETM425.pdf

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[Chris5156]

This topic must have made me a bit more alert to these things - today I spotted an open crossover on the M4 that I'd never noticed before.

Presumably this remains open because of the likelihood that the elevated section east of there will be blocked and traffic will need to be turned around. It's within the 40 limit so presumably the risk of an open crossover point is not so high.

[Conekicker]

This topic must have made me a bit more alert to these things - today I spotted an open crossover on the M4 that I'd never noticed before.

Presumably this remains open because of the likelihood that the elevated section east of there will be blocked and traffic will need to be turned around. It's within the 40 limit so presumably the risk of an open crossover point is not so high.

Very probably.

Another form of emergency access is this at the top end of the M18. It's the old alignment of the lane and is used by emergency service vehicles to turn around if needs be. It could be used to turn public traffic in a pinch. In theory it's gated, although you'll note the gates on both carriageways are almost always open - some of the locals use it as a "junction" and given the low presence of Humberside's finest on the network they get away with it.

[AndyB]

The posts are indeed markers to an ECP, Type 3 posts as shown here https://www.standardsforhighways.co.uk/ ... series.pdf

Interesting things I'm noticing...

The Type 2 (red stripe above blue band) was the original design for motorway nearside marker posts, and I think got replaced with the Type 1 to make the ID more visible? I've never seen one on a slip road, but I remember on the M1(NI) small blue plates with the telephone sign were attached as they must have been delivered without the label.

The Type 4 is used in NI on the D5 M2 foreshore, with index numbers in black on the white band (but now on the blue), although where a concrete barrier has been installed, they've been replaced by the 8B.

This is the curiosity that is marker post 0A38, which is theoretically impossible because there should only be marker posts 0-31 for each mile (spaced at 55 yards, don't ask why), but when the M2 was extended to York Street, it was made around 385 yards longer, and so eventually the Mile 0 marker posts were moved and extended.

[Alderpoint]

Not sure if this at the top of the M69 is a Emergency turning point, or just a gap in the armco.

[Conekicker]

Not sure if this at the top of the M69 is a Emergency turning point, or just a gap in the armco.

This curved paving indicates the whole paved area in the centre is intended for use as a crossover, the two lengths of barrier running through it being removed as needed. The gap is a neat way of allowing access for emergency or maintenance purposes between the two carriageways when the central reserve is so wide.

This on the M62, used for gritters, is a similar feature. Saves them travelling all the way to this turning point.

[jnty]

Given we're on the topic I'll bring up this one that's always taken my interest on the M6 north of Tebay: https://goo.gl/maps/1hSt55bwKdhA9yp27

It feels as though the legality of public use here would be at the very least arguable, although I suppose it does involve crossing the outer boundary line of the motorway. I once noticed that Google Maps had routed me this way when I accidentally navigated to the Tebay services on the wrong side! It's obviously been fixed now though.

[swissferry]

Not so much a turning point as removable barrier, the A90 allows for the road to be diverted onto the old FRB if the Queensferry Crossing is closed https://www.google.com/maps/@55.9796634 ... 384!8i8192

Similar on the other end, old road coned to the left, removable barrier in the centre https://www.google.com/maps/@56.0180447 ... 384!8i8192

AFAIK this has been trial ran.

That's Sologuard. There are quite a few installations on the motorway and trunk road network. Linky:

https://www.asset-vrs.co.uk/sologuard/

Given that the highway environment is an incredibly dirty place, the timing of just over 3 minutes shown on the video is optimistic to say the least. Absent frequent maintenance of the system, one might even say "brave". If you catch my drift.

The closure for the trial run of this a few years ago was several hours, I think, so no bravery involved! Of course there's more to redirecting the course of a motorway than just fiddling with a barrier though.

Automated Barriers to be Installed at Queensferry Crossing

[swissferry]

https://www.bearscot.com/queensferry-cr ... l-success/

[jnty]

https://www.bearscot.com/queensferry-cr ... l-success/

Fascinating. A rather tight turn at the diversion point!

[wallmeerkat]

https://www.bearscot.com/queensferry-cr ... l-success/

Fascinating. A rather tight turn at the diversion point!

It is, I assume that they were restricted by the length and angle of the movable barrier, I would hope that a temporary 30 limit is in place here



I wonder what the northern connection looked like, the temporary carraigeway should allow a shallow connection, or is traffic sent down J1B?

[jnty]

https://www.bearscot.com/queensferry-cr ... l-success/

Fascinating. A rather tight turn at the diversion point!

It is, I assume that they were restricted by the length and angle of the movable barrier, I would hope that a temporary 30 limit is in place here



I wonder what the northern connection looked like, the temporary carraigeway should allow a shallow connection, or is traffic sent down J1B?

It feels like sending the traffic down the junction would be a reasonable option, but there are similar temporary barriers there too.