Ideas to replace the Newark Flat Crossing!

[Nottingham59]

Can someone explain to me why it's considered so difficult to build a flyover at Newark? Given that the crossing currently only handles one or two movements an hour on the Notthingham-Lincoln line, you would only need a single-track straight viaduct, rising over the ECML. There seems to be plenty of space to do this. From the crossing, I measure 800m SW to the A46 bridge, and 1200m NE to the A1 bridge. And yet the new flyover at Hitchin only needed 660m to rise from the point of divergence to cross the ECML.

If ground conditions are poor, then you just need deep piles to support the pillars of the viaduct.

If vertical curvature is the problem, there is 400m between the A46 and Newark Castle station to dig down a bit so that you can go under the A46 on a rising gradient; and the crest of the viaduct could be 200m beyond the ECML crossing itself and still allow space to curve down and fit under the A1. (In which case the junction to access Northgate would have to be North of the A1 bridge, at which pont the line could become double-track again.)

Or am I missing something?

 

[MarkyT]

Can someone explain to me why it's considered so difficult to build a flyover at Newark? Given that the crossing currently only handles one or two movements an hour on the Notthingham-Lincoln line, you would only need a single-track straight viaduct, rising over the ECML. There seems to be plenty of space to do this. From the crossing, I measure 800m SW to the A46 bridge, and 1200m NE to the A1 bridge. And yet the new flyover at Hitchin only needed 660m to rise from the point of divergence to cross the ECML.

If ground conditions are poor, then you just need deep piles to support the pillars of the viaduct.

If vertical curvature is the problem, there is 400m between the A46 and Newark Castle station to dig down a bit so that you can go under the A46 on a rising gradient; and the crest of the viaduct could be 200m beyond the ECML crossing itself and still allow space to curve down and fit under the A1. (In which case the junction to access Northgate would have to be North of the A1 bridge, at which pont the line could become double-track again.)

Or am I missing something?

I remember many years ago there were some very heavy oil trains that used to cross fairly frequently from Immingham. I doubt many if any of those survive but you wouldn't want any freight or engineering trains getting stuck on a steep incline. At least at Hitchin, anything that couldn't make the flyover grade can use the flat junction.

 

[D365]

I don't imagine that building a single track viaduct would save much cost.

The cost of the design and construction, as well as the necessary weeks-long blockade, is likely why this proposal has been left on the back burner for years.

 

[MarkyT]

I don't imagine that building a single track viaduct would save much cost.

The cost of the design and construction, as well as the necessary weeks-long blockade, is likely why this proposal has been left on the back burner for years.

Also, a single track option would require additional PW expense for double to single track connections at either end, and associated more complex signalling.

 

[D365]

Also, a single track option would require additional PW expense for double to single track connections at either end, and associated more complex signalling.

Interlaced track?

Though that does defeat the object of my original post!

 

[najaB]

Someone will no doubt correct me, but I can’t think of any swing or drawbridge that has a linespeed of more than 75mph. And I know that 140mph wouldn’t be permitted where there are ‘permitted’ obstructions on the line even if they are proved clear (like level crossings).

The moving parts of the drawbridge would be on the Lincoln line (which is under 75mph I would have thought?), rather than on the ECML. That would be plain line. I thought the problem with level crossings at 140mph was mainly that they would have to close for too long for them to be of any practical use on a line that's busy enough to be specced for 140mph?

Like @MarkyT above, I don't expect this to ever be implemented, but it's interesting to think through the objections.

 

[Bald Rick]

That may be becasue the moving infrastructure itself is crossed by the train in question, unlike this example. You could deploy obstacle detection technology (radar/lidar) as well as conventional limit-switch detection of the mechanism and even supplemental Mk1 human eyeball 'crossing clear' checking via CCTV! I'm not recommending it though you must understand! I don't think there was ever an upper speed limit on MCB crossings.

Maximum for any level crossing is 125.

 

[Bald Rick]

The moving parts of the drawbridge would be on the Lincoln line (which is under 75mph I would have thought?), rather than on the ECML. That would be plain line. I thought the problem with level crossings at 140mph was mainly that they would have to close for too long for them to be of any practical use on a line that's busy enough to be specced for 140mph?

Nope, the problem is that the consequences of a collision at an LX get exponentially worse with speed, and 140mph is rather worse than 125. Of course 125 is much worse than 100, and that is one reason why the ECML sticks out like a sore thumb.

Also, the issue is not on which line the moving parts are connected; the issue is the line upon which an obstruction is created.

 

[Ianno87]

Maximum for any level crossing is 125.

I presume that's a safety imposed restriction rather than a technical one?

i.e. one could design a level crossing that technically operates at 140mph...it's just over the threshold for being unwise to do so given the consequences of a collision at that speed.

 

[Nottingham59]

Thanks for the replies, folks.

I doubt many if any of those survive but you wouldn't want any freight or engineering trains getting stuck on a steep incline.

But you only have to rise about 6 metres over 800m. Even allowing for vertical curves, that's a maximum gradient of less than 1 in 100. Surely any freight train should be able to manage that?

I don't imagine that building a single track viaduct would save much cost.

So build a double track viaduct. Maybe it's just the expense rather than any technical problem that has left this unresolved for years. And anyway, it's getting to be irrelevant now: with HS2 phase 2 taking most of the long-distance ECML traffic, there won't be the pressure on paths in the future, and more trains on the ECML will presumably be stopping at Newark Northgate.

 

[Bald Rick]

I presume that's a safety imposed restriction rather than a technical one?

i.e. one could design a level crossing that technically operates at 140mph...it's just over the threshold for being unwise to do so given the consequences of a collision at that speed.

Yep that is my understanding. The line has to be drawn somewhere, and it is at 125mph.

Which leaves me to ponder, how many public highway Level Crossings are there out there with a 125mph linespeed? Loads on the ECML, Cove, Floriston, Hest Bank and one more on the WCML, a few on the GWML, and that’s it I think?

 

[D365]

ECML level crossings have to be removed eventually, but (as with the Newark flat crossing), it’s a case of funding, or lack thereof.

Several level crossings south of Peterborough were slated for replacement this decade, I wonder why this project appears to have stalled.

 

[class26]

Yep that is my understanding. The line has to be drawn somewhere, and it is at 125mph.

Which leaves me to ponder, how many public highway Level Crossings are there out there with a 125mph linespeed? Loads on the ECML, Cove, Floriston, Hest Bank and one more on the WCML, a few on the GWML, and that’s it I think?

Correct me if I am wrong but my understanding is that the number of crossings between Birmingham and Bristol is the reason line speed is limited to 100 mph

 

[class26]

Yep that is my understanding. The line has to be drawn somewhere, and it is at 125mph.

Which leaves me to ponder, how many public highway Level Crossings are there out there with a 125mph linespeed? Loads on the ECML, Cove, Floriston, Hest Bank and one more on the WCML, a few on the GWML, and that’s it I think?

............and IF these crossings were removed once in cab signalling is all working could line speed be increased to 140 mph where appropriate on the ECML ?

 

[Bald Rick]

Correct me if I am wrong but my understanding is that the number of crossings between Birmingham and Bristol is the reason line speed is limited to 100 mph

The crossings will be a factor, but not the only factor.

 

[Bald Rick]

............and IF these crossings were removed once in cab signalling is all working could line speed be increased to 140 mph where appropriate on the ECML ?

No, as has been said several times previously, there’s a lot more that would need sorting, not least the track, the OLE, structure strengthening, gauge clearance ... and all for 3 seconds a mile.

 

[class26]

No, as has been said several times previously, there’s a lot more that would need sorting, not least the track, the OLE, structure strengthening, gauge clearance ... and all for 3 seconds a mile.

In that case it seems strange that the DFT were including 140 mph in the IEP specs if they were aware that it would cost alot for such small gains ?

 

[Halifaxlad]

Instead of trying to create a flyover at Newark, what about reinstating the Spalding - Boston, Boston - Lincoln, Lincoln - Tuxford lines and then creating a new chord at Tuxford off the ECML so that some services could be routed via Lincoln ?

 

[30907]

Instead of trying to create a flyover at Newark, what about reinstating the Spalding - Boston, Boston - Lincoln, Lincoln - Tuxford lines and then creating a new chord at Tuxford off the ECML so that some services could be routed via Lincoln ?

Given that there is an existing route from Spalding to Doncaster, which services would use which of these lines?

 

[class26]

Given that there is an existing route from Spalding to Doncaster, which services would use which of these lines?

Out of the three routes suggested I think the first one has merit but the other two would be low down the list of lines to re open. I say that being born on the Boston to Lincoln line (Coningsby) which has in the last 30 years grown into a small town

Boston - Spalding would open up direct services to London either via a change at Peterborough or direct (after HS2 when paths would be freed up). If this was open there MIGHT be some sense in opening Lincoln to Boston direct as this would give Woodhall Spa and Coningsby a route via Boston to London.

I know Lincolnshire is often overlooked, considered to have too low population and there`s always more deserving causes elsewhere etc, etc but the population of this area is growing fast and Lincolnshire people are by and large surgically attached to their cars but the road system is dreadful and unlikely to be much improved. At some point I think Boston - Spalding ought to be looked at even though the old trackbed is now the A16 then consider Lincoln - Boston as a follow on. Lincolnshire metro ?

I can`t see why services coming off the ECML at Tuxford for Lincoln would have much use when they and do can now leave at Newark. Also going on to Tuxford would be another service crossing the Lincoln - Nottingham line

 

[Jorge Da Silva]

I like the idea of a Lincolnshire Metro! Do we need a separate thread?

 

[class26]

I like the idea of a Lincolnshire Metro! Do we need a separate thread?

Why not? No doubt it will be scorned by some for the usual reasons but as i said above the population is growing fast with many new houses being built but the roads are not improving and were dreadful before the growth in population
Even the small towns such as Sleaford have dreadful traffic and as for Boston , i hardly ever drive there but take the train. Locals in my village (Heckington) think I am so very strange taking the train, they would rather sit 30 mins in a jam than take the train. There are even some that aren`t aware there is a train into Boston !

I have no idea how to start a new thread but let me kick it off here-

Firstly I would go for park and rides for Lincoln (Cherry Willingham and Washingborough) ) and Boston (Hubberts Bridge and Sibsey). This might mean doubling the Poacher line service to half hourly so once an hour all stops for park & ride, the other limited stop for those travelling further. Frequency gets people, out of cars as we all know.

These new services from Boston could be routed alternately to Peterborough at Sleaford for faster service to London and to Doncaster for better connections to the north.

Re openings on existing lines ought to be Donington and Gosberton.

This i reckon would have a dramatic effect on rail possibilities in southern Lincs

That`s my two penny worth. Over to others ................................

 

[Jorge Da Silva]

https://www.railforums.co.uk/threads/ideas-for-a-lincolnshire-metro.204323/

Here is the thread

 

[Halifaxlad]

Given that there is an existing route from Spalding to Doncaster, which services would use which of these lines?

Obviously some existing ECML services!

I can`t see why services coming off the ECML at Tuxford for Lincoln would have much use when they and do can now leave at Newark. Also going on to Tuxford would be another service crossing the Lincoln - Nottingham line

The idea was to reduce the use of the crossing that would eliminate the need for a fly over.

 

[High Dyke]

Has anyone suggested a spiral to gain the height to cross the ECML? On the Sugar factory side there is probably sufficient space after passing under the A46 bypass. The section east of the River Trent toward the A1 could be a bit more problematic due to the close proximity of the A46 on one side and the sewage treatment plant on the other.

 

[Bald Rick]

Has anyone suggested a spiral to gain the height to cross the ECML? On the Sugar factory side there is probably sufficient space after passing under the A46 bypass. The section east of the River Trent toward the A1 could be a bit more problematic due to the close proximity of the A46 on one side and the sewage treatment plant on the other.

I’m not sure whether you are being serious or not, but just in case you are, why? There’s enough space to get up and down on a ‘normal’ flyover.

 

[High Dyke]

I’m not sure whether you are being serious or not, but just in case you are, why? There’s enough space to get up and down on a ‘normal’ flyover.

It was, after all, a speculative idea... However, why not a consideration? The River Trent navigation at Nether Lock, right next to the Flat Crossing would also need to be bridged. OK, a flyover should overcome that obstacle at the same time. Is there sufficient space from the Newark Castle station side to gain a sufficient rise in gradient, at a suitable incline for freight trains to ascend without issues? Alternatively, is it worth considering replacing the current A46 viaduct with a new structure that has the road and rail side by side over the rise and fall - even divert the A46 to a new alignment further north.

 

[Bald Rick]

Is there sufficient space from the Newark Castle station side to gain a sufficient rise in gradient, at a suitable incline for freight trains to ascend without issues?

Yes, comfortably. From the A46 overbridge east of Newark castle to the ECML is as near as makes no difference 800metres. The rail level of the flyover will need to be 7 metres above the ECML rail level. Allowing for vertical transitions that still allows for a gradient of 1:100 for less than half a mile. Compare to Shap, or Stormy Bank, or any other number of climbs that regularly see long, heavy freight trains.

 

[Ianno87]

Has anyone suggested a spiral to gain the height to cross the ECML? On the Sugar factory side there is probably sufficient space after passing under the A46 bypass. The section east of the River Trent toward the A1 could be a bit more problematic due to the close proximity of the A46 on one side and the sewage treatment plant on the other.

The squealing from the flanges could be heard across vast swathes of Nottinghamshire, and possibly parts of Lincolnshire...

 

[MarkyT]

Yes, comfortably. From the A46 overbridge east of Newark castle to the ECML is as near as makes no difference 800metres. The rail level of the flyover will need to be 7 metres above the ECML rail level. Allowing for vertical transitions that still allows for a gradient of 1:100 for less than half a mile. Compare to Shap, or Stormy Bank, or any other number of climbs that regularly see long, heavy freight trains.

Sounds reasonable, and you've got about the same distance from the sewage works road crossing to the A1 bridge on the east side. Freights would usually be able to get a run at the grade so you wouldn't lose much speed and time. It'd certainly be a lot better than getting an unplanned regulation stop before crossing on the level and getting back up to speed again.