Can someone clarify the situation on WCML southern end which appears to be "full", but doesn't seem to have anything like as many trains as 4-track capacity would suggest was available. With 3 minute headway and 4 tracks and nothing in the way (like a stopper), and say 12 trains on each track per hour, isn't that say 24 northbound and 24 southbound per hour which I doubt happens.
Whilst I realise that there will be morning and evening peaks, so it will vary dependent on time of day, in general
-On the slow lines (and possibly some fast), capacity is soaked up by Emus stopping at stations where there is no loop to platform off main line or they catch up service in front
*how much of this is caused by trains stopping at stations on slow lines
*could new loops with platforms be added to ensure that stopping trains didn't block the slow lines
*if so how many stations affected
*how difficult / expensive would it be to source trains with near identical chgaracteristics?
*from where (south) to where (north) are these emu? paths an issue?
-Obviously freight absorbs some capacity on slow lines at southern end of WCML
*how many freight paths are there per hour?
*how many are used?
*from where (south) to where (north) are these freight paths an issue?
-How does usage level of 4-track WCML compare to 4-track MML in terms of trains / hour?
-How much is congestion at Euston affecting usage?
I am by no means an expert on the WCML timetable (
@The Planner is), but to answer some of your questions, in no particular order:
There are nominally 3 freight paths on the WCML in the standard hour, two on approximately standard timings, and the third goes where it can fit in. None of these run in the peak hours peak direction, as there are extra passenger trains.
Path usage varies through the day / week / year. Fridays are quieter, autumn is busiest. But, typically they are all used at some point during the week, and at least half are used every day.
The timetable is constructed such that trains make use of ‘shadows’ left by other trains. For example, the freight paths come in at Camden in the hole left by the DC services leaving the slow lines there. The LNR fast that crosses down fast to down slow at Ledburn Junction drops in between 2 MK terminators (one LNR, one Southern), and effectively take the path of the former north of MK. One of the standard freights fills the gap created by 20 minute gap in Euston slow line departures between the xx04 (Tring stopper) and xx24 (Rugeley semi fast), but at Tring the freight is 4 minutes behind the former and 5 minutes in front of the latter. The other standard freight path has the same slot on the opposite half hour.
Many of the freights join at Camden, then dive off at Wembley for crew relief or other purposes (it’s the first opportunity from Ipswich / Gateway / etc) before rejoining.
Because of the varying stopping patterns, and different times needed to clear junctions / accelerate (ie between a 4 car 350 and 700m long Freightliner) just about everything is on or close to minimum headway somewhere on its journey between Euston and MK. There will be gaps in some places, but you can’t fill them because the gap doesn’t exist further along the line.
My best advice would be to draw it all on a piece of graph paper, and you’ll find it a very busy bit of paper!
Euston congestion - for trains - isn’t an issue, the layout was designed very well. However passenger congestion at the station is a worry, and the station wouldn’t be able to take many more in the way of passengers without a major rebuild, and neither could the tube station. Happily HS2 solves those issues.
Station loops are rarely the answer, as the ‘looped’ train loses a minimum of 5 minute sjourney time, often more. To avoid this you need dynamic loops, covering at least 2 stations plus half a mile or so each side. Then you are building two new tracks right alongside, and rebuilding stations and all the cost and disruption that brings. And ultimately, it doesn’t create many paths, as the looped train needs two.
The WCML South of MK is pretty similar to the MML south of St Albans, but the WCML is much busier for much more of its length.
MML Standard hour has 5 EMT and 10 Thameslink departures from St Pancras (ignoring the 2tph Thameslink to Kentish Town). Plus 2 freight. 17 total, 11 north of Luton, 7 north of Bedford.
WCML has 12/13 fast line departures from Euston, plus 4 slow line (ignoring the 3-4tph to the D.C. lines), plus the Southern service joining at Wembley, and the three freight. 20/21 total, 16/17 north of MK (generally to Rugby).