I have been covering over the last few weeks options for locations for large Garden Cities to cover long term growth options in the greater south east including the huge 600,000+ overspill from London implied by the latest London plan targets.
This post covers Kent, Surrey and Sussex.
In one sense it is the easiest area as it will need to take least overspill. My model looking at NPPF unconstrained areas within 100km of London suggests only 11% of the overspill can go within this three counties, because of sea and constraints.
In other ways it is the most difficult, because of constraints and its own population growth, adding overspill to indigenous growth implies over 1.2 million new homes here by 2050.
As it has a dense existing settlement stricture and is not central to the UK a smaller proportion of growth here will need to go to new strategic developments as opposed to organic growth of existing settlements. 1.2 million new homes though will put pressure on these settlements . I assume therefore around 50% of growth will be new strategic locations (as opposed to my 75% assumption for the Oxford-MK_Cambridge corridor).
Its not easy finding sites for 600,000 new homes.
I assume Kent will take the major share as being most accessible and less constrained than Sussex or Surrey. Where then could you fit 400,000 or so additional houses in Kent? Equivalent to two large Garden Cities of 200,000 population each, or more likely two of around 150,000 each and expansion of existing planned Garden Communities such as at Folkstone and Paddock Wood to cover the remaining 100,000.
Folkstone and Paddock Wood are of Course on the original route of South Eastern main line now known as the Redhill-Tonbridge-Ashford line . Two track and third rail not promising, as well as feeding into Charing Cross, which was deemed too small a site from the day it was planned in the nineteenth century, however it is the straightest railway line in the world and has surprisingly little development along it, with many settlements on one side only as the first line from London to Dover and forced to take a sharp southern line first as the Admiraty objector to tunneling under Greenwich observatory serving settlements was a secondary consideration) and in towns such as Ashford and Paddock Wood already four track.
My bold solution is to separate fast and stopping services by extending Crossrail II via a 5 mile tunnel from Chessington to Redhill linking to the South East Mainline and diverting all fast services from Charing Cross (you could still catch a slow train to Clapham Junction and change there) – from there it would be limited stop high speed rail all the way to Ashford and the Eurotunnel, also serving a parkway station for the Garden City planned at Otterpool Park (Which I first suggested). I term this the Garden of England line.
The lack of development along the route makes it surprisingly easy, only a few dozen houses would be affected as it mostly passes through Greenfield and industrial.
South of Chessington I would build a parkway station to serve Epsom and Letherhead with a release of Green Belt at Maldon Rushett so London also bears its fair share. TEast of Paddock Wood is outside the Green Belt and probably 75% of this growth alongside this corridor.
The relief tracks would be laid first, then the stopping services would use these whilst the old stopping lines were upgraded to high speed.
What this then does it free up perhaps nodes for communities of 10-60,000 each at locations such as South Godstone, Edenbridge, Leigh, Staplehurst, Marden, Headcorn and Pluckley. the fast services would be interleaved so that every other fast service covered one of these stations. The largest nodes would be between Tonbridge and Ashford as this would be closest aligned with infrastructure in all its forms (though a new link A road would be needed from Tonbridge to the M20). This would then also form a linear city (with extensive green gaps) also facilitating BRT between Tonbridge and Ashford through the new nodes.
I would term this Garden City Gramarye (its a reference to Kipling who wrote poems about the Weald)
With pressure on routes through Croydon reduced it would free up capacity on the Brighton mainline enabling some growth on the narrow low weald gap here.
This area is not easy, its full of ancient enclosures, orchards, oast Houses, ancient woods and boggy clay fields, it would need outstanding design and extensive run off and green areas. however it is far less sensitive than the high weald, downs and green sand ridges, as well as ancient villages and small towns elsewhere in Kent, it also diverts teh vast majority of the growth outside the Green Belt.