No, there isn't anything like the demand to justify the enormous expenditure that this proposal would require, even using on street running.
The existing curve is on the limit for trains, your curve is substantially tighter. It also goes through a house which has a market value probably not far off the cost of your proposed curve.
Reinstatement beyond the buffers at Bourne End would be enormous expenditure because houses have been built opposite, so you're looking at either demolition or on-street running in a town with fairly small, tight and twisty roads. You could probably convert the existing formation without too much fuss although whether the rebuild of the stations offsets the cheaper OLE infrastructure I'm not sure.
Edinburgh Trams are being extended to Leith at a cost of £207 million for 2.67 miles - source. The distance between Bourne End and High Wycombe Station via Loudwater is about 7.1 miles, ie nearly three times that. There is also the cost of a passing loop at Cookham and the rolling stock. So, a good part of £750 million - £1 billion I would imagine. That does seem like enormous expenditure for something that it is not clear would really be that useful and just fills a gap on the railway network.
www.roads.org.uk
Genius idea! Would even allow 4 car Electrostars on the Marlow branch line!
But that's solved with a passing loop somewhere near Cookham...
The curve is extremely tight even with its present configuration, moving the junction towards Maidenhead makes it even tighter. The line to Maidenhead curves slightly away to make matters worse.
Money. No one wanted to pay for the ongoing costs of that stretch of line, i.e. staffing the numerous gated level crossings.
I don't think it is sensible to compare the cost of building a line in semi-rural Buckinghamshire with entirely on-street route through an inner city. That said, it won't be anything like cheap either, at least £30m per mile and probably worse, so just as unaffordable, even if the number is smaller
Much of the traffic is or was London commuting. Loudwater and Wooburn Green perhaps looked to Beaconsfield on what became Chiltern, rather than the longish run via Maidenhead or going away from London via High Wycombe. Even in BR(W) days, the through trains to Paddington started or terminated at Bourne End. Being on the Thames, Marlow, Bourne End and Cookham may have provided more commuters anyway.
I imagine far more people in Marlow or Bourne End would want to go to Maidenhead than High Wycombe, as there are more useful places on the GWR route (Heathrow, Slough, Reading) than on the Chiltern Line, which back then was being run down anyway
Marlow supports a frequent bus service into High Wycombe which goes past the main areas of population (some of which wasn't built in 1970). High Wycombe Station isn't in a great location for the town and neither is Marlow. The route via Bourne End to High Wycombe isn't exactly direct.
Are details publicly available?
Thanks - I don't remember reading it in RIS2, but I only read it once around the time it came out, so to be honest I don't remember much from the document!
Err, why? Standard highway clearance of 16' 6" would be provided as any other crossing.
