§ Mr. David Watkins
asked the Secretary of State for the Environment (1) what was the average rate of return expected and realised in each of the financial years from 1970–71 to the latest available date in investments in road construction;
(2) What was the test discount rate as applied in respect of loans made to nationalised industries in the financial years between 1st April 1970 and 31st1198W
six-lane motorway; and how they compare with regards space taken up.
§ Dr. Gilbert
The capacity of both double-track railways and six-lane motorways depends on many variables. These include whether passengers or freight are involved, the types of vehicle and traffic, the safety, or signalling, standards, speed levels, and gradients. These variables affect railways and motorways differently. It would, therefore, be very difficult to present briefly any absolute comparison.
On the second part of the Question, present design standards for the carriageways and hard shoulders of a rural dual 3-lane motorway involve taking up about 13 acres per mile. An estimated equivalent figure for a double-track railway would be about 3.2 acres. The total land taken in each case, including that for embankments and other associated works for railways and roads, varies considerably according to the nature of the works required and the terrain.