There is nothing really wrong with the signalling at Worcester. I know that mechanical systems might appear to be 'old fashioned' but mechanical signalling can be, and is, a lot more flexible than modern colour-light signalling in station areas. What really needs sorting at Worcester is the re-instatement of double line working between Shrub Hill and Henwick (which would be a fairly simple job to achieve).
That would actually be a
much bigger job than redoubling to Evesham. It would entail restating Rainbow Hill Jn; it wouldn't really be worth doubling from SH to there as that section would be really short, so one would want to have a facing crossover between Foregate St and RHJ so trains from Malvern/Hereford can get to the SH line. The same crossover would also allow terminating trains from Birmingham to continue running into P2 at FS as they do now and those from or London/Oxford/Bristol/etc to do the same using either platform.
But to make this work you'd need to address the present anomaly whereby the signal (HK5) reading from FS P1 to SH is controlled by Henwick but the one opposite it, (TJ20) from FS P2 towards Tunnel Jn, is controlled by the latter. Without a full Worcester resignalling, it probably makes most sense for Henwick to control all of the FS area through to RHJ (inclusive). With the layout as envisaged above, this would require signalled moves for:
- SH line to P1
- SH line to P2
- TJ line to P1
- SH line to P2
- P1 to SH
- P2 to TJ
- P2 to SH
ie a total of seven routes in place of the one currently worked from Henwick (HK5), plus two more if you add routes directly from FS into the up siding at Henwick. In addition there would be two extra sets of points, to/from the SH branch and the facing crossover.
And, if you were doing this, it would also be sensible to resolve the situation of Henwick's down homes being so far in rear of the level crossing and yet not having distant/repeater arms for the down starter which must be almost a mile beyond them. Ideally these should be replaced with 4-aspect signals, with additional 3-aspect ones a short distance before the
LC▸ . But this would add two further signalled routes.
At the moment there are only seven free spaces in Henwick's 25-lever frame. One more lever could be freed up as an acceptance lever from TJ would no longer be needed. So only the most the basic version could be squeezed in at all, even if you could get the required new levers manufactured and a very significant re-locking of the frame done. (More levers could be freed if you decided to abolish either or both of the existing crossovers at Henwick, but that would come at the cost of significantly less flexible layouts and entail even more signal/locking changes.)
In practice, therefore, a new panel would be all but essential, and once it's decided to go for a panel one may as well resignal the whole Henwick area. The latter would at least be a useful stage work on the step towards full Worcester resignalling.
[I am assuming the block sections would be
TCB▸ from TJ to RHJ (because Henwick won't see trains' tail lamps until/unless they run on towards Malvern); the other direction could be AB because TJ can see the tail lamps as trains pass; and RHJ-SH would continue worked by acceptance levers as the single-line section from SH is currently. Another point one would have to consider is whether it makes sense to have a separate new signal at RHJ on the line from SH, or whether the signals controlling the routes into the FS platforms shouldn't somehow be combined with SH75 on the Shrub Hill down advanced starting bracket.]