'Higher Speed' Lines by bypassing slow sections with new track

[edwin_m]

National Highways are shortly expected to submit a DCO application to upgrade the A46 around the west of Newark and A1 junction.

Preferred Route announcement (linked below) does suggest that the scheme has been designed to accommodate any future Network Rail scheme to remove the flat crossing.

https://s3.eu-west-2.amazonaws.com/assets.nationalhighways.co.uk/roads/road-projects/A46+Newark+bypass/Final+BHM22_0012+A46+Newark+bypass+PRA+brochure_v2.pdf

It doesn't actually say that.

We have worked with Network Rail and the Department for Transport to identify and understand any conflicts between the A46 Newark Bypass scheme and potential rail schemes, and to discuss opportunities for working together. As a result, we identified a location immediately to the east of the sewage works underpass where the schemes would be very close together. We have changed the layout of the eastbound off-slip to Brownhills roundabout to increase the space between the railway and the road so that a future rail scheme would not be prevented by our scheme. We will continue to work together as the design of both schemes is developed.

So they have made changes to the sewage works area, which I believe is close to the ECML, but there is no mention of any change near the Cattle Market junction where the existing road over the railway is to be dualled. This text doesn't rule out that they may be keeping the adding a new bridge, higher if necessary, for the new carriageway but keeping the existing one next to it. That's what happened with the A453 dualling near East Midlands Parkway, and the splitting of the carriageways on the map suggests that separate structures may be intended.

I suggest the gradient needed for the existing bridge could be marginal for a distance of 800m. Network Rail likes 1 in 100 or better, and the existing route is pretty flat so a short section with a severe gradient could compromise the maximum loading of freight trains (including some very long oil trains).

 

[Ken H]

A more frequent service would be needed to take more cars off the A46, which will need more upgrades otherwise. So it's not just about the rail picture.
And the potential to increase service on the ECML after other improvements are made helps the long-term strategic case.

But the A46 comes through Leicester, not Nottingham. More Nottingham - LIncoln trains wont help the A46. Remember the A46 is the Coventry bypass, where it turns into the M69. So its dual carriageway from the M40 to Newark except for 1 roundabout (Northbound only) at Cheylesmoor, coventry, another where the cov-rugby road crosses the A46 and one more near Syston.
Oh and one at M1 Jct 21 southbound.

Have to be a good railway to entice people off that.

 

[Nottingham59]

I suggest the gradient needed for the existing bridge could be marginal for a distance of 800m. Network Rail likes 1 in 100 or better, and the existing route is pretty flat so a short section with a severe gradient could compromise the maximum loading of freight trains (including some very long oil trains).

The loaded oil trains run westbound, so have 1200m from the A1 bridge to get up over the ECML. At 1 in 100, that's 12m.
Even allowing for transition curves, I'd have thought that would be more than sufficient. How thin can a rail-on-rail overbridge be? And what clearance above the rail is needed for W12 with electrification?

See for instance 6M35 and 6M57 had trailing loads of 3200t today, with the eastbound 6E46 and 6E54 at 1000t.

Realtime Trains | Departures from Nottingham all day on 06/03/2024

Train information at Nottingham all day on 06/03/2024. From Realtime Trains, an independent source of train running info for Great Britain.

www.realtimetrains.co.uk

 

[WideRanger]

But the A46 comes through Leicester, not Nottingham. More Nottingham - LIncoln trains wont help the A46. Remember the A46 is the Coventry bypass, where it turns into the M69. So its dual carriageway from the M40 to Newark except for 1 roundabout (Northbound only) at Cheylesmoor, coventry, another where the cov-rugby road crosses the A46 and one more near Syston.
Oh and one at M1 Jct 21 southbound.

Have to be a good railway to entice people off that.

I think people are talking about the Nottingham - Lincoln corridor. Which, if you are doing it by car without going a very 'scenic' route, means taking the A46 through Newark.

 

[class26]

A more frequent service would be needed to take more cars off the A46, which will need more upgrades otherwise. So it's not just about the rail picture.
And the potential to increase service on the ECML after other improvements are made helps the long-term strategic case.

Indeed. Everywhere else it seems greater frequency is the answer but when it comes to places like Lincs it suddenly isn`t.

 

[Bald Rick]

Everywhere else it seems greater frequency is the answer but when it comes to places like Lincs it suddenly isn`t.

Not so. Capacity is usually the answer. Frequency is one way to achieve this. But a far more effective way is longer trains where the infrastructure can accpet it.

 

[Austriantrain]

Not so. Capacity is usually the answer.

In a demand-led timetable, yes. If it were supply-led, frequency would be more important (up to a point).

 

[eldomtom2]

Not so. Capacity is usually the answer. Frequency is one way to achieve this. But a far more effective way is longer trains where the infrastructure can accpet it.

Capacity is not always the answer. A lot of people will not use a train with infinite seats that only runs two times a day.

 

[AlastairFraser]

Indeed. Everywhere else it seems greater frequency is the answer but when it comes to places like Lincs it suddenly isn`t.

Agreed
It's about future proofing too. If you extended the rolling stock and induced more demand, then you need to increase capacity.

 

[Bald Rick]

Capacity is not always the answer. A lot of people will not use a train with infinite seats that only runs two times a day.

Hence the word ‘usually’, and not ‘always’. And in the case I was referring to, there are rather more than 2 trains a day.

 

[eldomtom2]

And in the case I was referring to, there are rather more than 2 trains a day.

Yes, but 1 train per hour is still far below the point at which adding frequency primarily serves to add capacity rather that drive ridership.

 

[The Ham]

Yes, but 1 train per hour is still far below the point at which adding frequency primarily serves to add capacity rather that drive ridership.

Anything at or less than 1tph really needs an increase in frequency. However after that, lengthen trains as more capacity is needed.

In part, as 3tph each with 4 coaches is more expensive to run than 2tph with 6 coaches. However lengthening soon reaches a capacity when more trains are then need (for example 12 coaches), however for many places it's shorter than that due to platform lengths.

 

[Bald Rick]

Yes, but 1 train per hour is still far below the point at which adding frequency primarily serves to add capacity rather that drive ridership.

It’s been along day/week/month.

I think I know what point you are trying to make, and all the individual words seem likely to be appropriate, but I can’t get them in the right order to make sense.

I can’t tell if you are suggesting that spending upwards of half a billion quid on a new flyover that would enable a few more Lincoln to Nottingham trains to run would be better value than adding a couple of coaches to the existing trains, or not.

 

[Grimsby town]

It’s been along day/week/month.

I think I know what point you are trying to make, and all the individual words seem likely to be appropriate, but I can’t get them in the right order to make sense.

I can’t tell if you are suggesting that spending upwards of half a billion quid on a new flyover that would enable a few more Lincoln to Nottingham trains to run would be better value than adding a couple of coaches to the existing trains, or not.

I get your point that lengthening trains is more cost effective, but the impact of frequency shouldn't be underestimated. On shorter journeys it really one of the most important, if not the most important factor. Lincoln to Nottingham is a relatively short journey so frequency would definitely help drive demand.

Lincolnshire certainly suffers from a lack of infrastructure even considering its relatively low population density. Unlocking the capacity constraints at Newark is probably the biggest improvement to the Lincolnshire rail network that would actually be somewhat feasible.

 

[eldomtom2]

Anything at or less than 1tph really needs an increase in frequency. However after that, lengthen trains as more capacity is needed.

Depends on the context - most people wouldn't ride the tube if the trains had infinite capacity but only came once every half hour...

I can’t tell if you are suggesting that spending upwards of half a billion quid on a new flyover that would enable a few more Lincoln to Nottingham trains to run would be better value than adding a couple of coaches to the existing trains, or not.

I am not for or against this specific suggestion; I was responding to your attitude that capacity is far more important than frequency.

 

[Bald Rick]

I am not for or against this specific suggestion; I was responding to your attitude that capacity is far more important than frequency.

Can you show where i displayed that attitude?

What I said was:

Capacity is usually the answer. Frequency is one way to achieve this. But a far more effective way is longer trains where the infrastructure can accept it.

 

[The Ham]

Depends on the context - most people wouldn't ride the tube if the trains had infinite capacity but only came once every half hour...

Indeed, clearly there comes a point when lengthening trains is practically impossible (typically on the existing network this maxes out at 12 coaches, however 16 coaches for new build like HS2 could still be viable).

In the context of 1tph doubling the frequency (even if the trains are only two coaches long) would make rail far more attractive than running a single train with 6 coaches.

 

[eldomtom2]

Can you show where i displayed that attitude?

What I said was:

I interpreted that post as treating capacity as more important than frequency.