§ Mr. MarlowTo ask the Secretary of State for Transport if, pursuant to the answer of 11 July, he is in a 333W position to provide the estimates on motorway capacity requested by the hon. Member for Northampton, North using the following illustrative assumptions: midsummer, five miles from the nearest junction, dry conditions, midday; and if he will make a statement.
§ Mr. Peter BottomleyNot precisely in the conditions suggested. Observations have been made for the highest sustainable flow over a one-hour period in good conditions and with no disruptions such as accidents. For motorways the average speed of the traffic in these conditions was about 50 mph. When heavy goods vehicles constituted about 12 per cent. of the total traffic, the observed flows on three lanes was about 6,000 vehicles per hour.