Your reference to the high cost per kilometre of the Coulsdon bypass (NCE 22 June) is perhaps a reection of the standards adopted.
At the northern end of the site an existing 1m high wooden fence has been removed to be replaced - it is understood - by a 1.5m high wall. This has necessitated digging a 2m deep, 2m wide trench.
On this has been cast the wall foundation, which is of reinforced concrete 1m wide and 1m deep - the sides of which have been carefully brushed with bitumen.
Needless to say the ground is good chalk.
I await further developments.
Francis Walley, 13 Julien Road, Coulsdon, Surrey, CR5 2DV