Ipswich Bacon chord

[HowardGWR]

The A14 is to bypass having to drive through the already congested town centre. The current rail line through Ipswich doesn't have that problem.
Given that there's no pressing need for the line to go South of the town centre, it's far easier to go on the flat(ish), North of it, than it is to build a relatively huge bridge.

Thanks for the two replies. You gather I was just looking at a map. Incidentally, I did not realise it was hilly south of Ipswich. I once went to Harwich for the ferry and thought it was flat around there. Also by the way, I was not envisaging following the A14 to the west of Ipswich from Felixstowe but joining the line through the station area northwards to rejoin the line near the bacon factory, but perhaps it would make it too congested there?

I've had a look through Street View now and see the point, although a swing bridge perhaps might have been used (beware drunken Russian skippers though).

 

[JGR]

Thanks for the two replies. You gather I was just looking at a map. Incidentally, I did not realise it was hilly south of Ipswich. I once went to Harwich for the ferry and thought it was flat around there. Also by the way, I was not envisaging following the A14 to the west of Ipswich from Felixstowe but joining the line through the station area northwards to rejoin the line near the bacon factory, but perhaps it would make it too congested there?

I've had a look through Street View now and see the point, although a swing bridge perhaps might have been used (beware drunken Russian skippers though).

It's not really hillier, per se, sorry for being unclear. It's more that the plateau of the surrounding land is noticeably raised above river/town centre level (google suggests about 35m), but probably not really enough for a long straight bridge from one plateau to the other to be high enough for ships.
For some kind swing bridge, you'd probably need to ramp down and up the banks, it'd also have to be quite a big swing, or otherwise you'd need to ramp up and over like the A14. Both options sound rather expensive.

 

[snowball]

Also by the way, I was not envisaging following the A14 to the west of Ipswich from Felixstowe but joining the line through the station area northwards to rejoin the line near the bacon factory

What would be the purpose of that, given that there is already a line from Felixstowe round the north of Ipswich to the main line?

 

[HowardGWR]

What would be the purpose of that, given that there is already a line from Felixstowe round the north of Ipswich to the main line?

It was The Planner's comment that the present line could not be doubled over a viaduct (Spring viaduct was it?).

 

[snowball]

It was The Planner's comment that the present line could not be doubled over a viaduct (Spring viaduct was it?).

Found the post now. It's Spring Road viaduct. Looking at it on Google satellite view and Streetview, it's fairly tall, short and in a generally urban area but does not seem to have buildings or private gardens close to it.

If it was absolutely necessary to double track the whole of the branch, you could build a new viaduct alongside for the second track, and I imagine this would be much cheaper and less intrusive than building a completely new route elsewhere.

However, to get a substantial benefit for reasonable cost, I imagine it would be best to double track some rural sections with few bridges, such as between Trimley station and Levington, and leave the rest single.

 

[Chris125]

There is a bottleneck on the alignment at Camden West junction. THere would need to be some land purchase and demolition. But that wouldn't be a huge cost.

Cost is relative - quadrupling that junction, along with the reinstatement of the four-track formation through Camden Road, would be a massive expense for a very limited benefit.

While it's an undeniably 'neat' solution the benefits to east-west travel don't go much beyond avoiding the need to use the NLL. A through service may be preferable to changing at Willesden and/or Highbury, but not at the expense of a direct service to Euston and it's potential impact on freight paths.

Chris