HC Deb 23 February 1973 vol 851 cc227-8W
Mr. Spearing

asked the Secretary of State for the Environment if he will tabulate in the OFFICIAL REPORT the flow that can be expected in "passenger car units" in one direction on a three lane urban motorway at a design speed of 50 miles per hour with the equivalent flows in vehicles per hour with 10, 20 and 30 per cent., respectively, of the traffic flow consisting of heavy goods vehicles.

Mr. Peyton

I would expect flows of over 6,000 passenger car units per hour on one carriageway of a dual three-lane urban motorway at speeds slightly in excess of 50 mph and with 10 per cent. of heavy goods vehicles.

Similar flows are expected with the higher percentages of heavy goods vehicles quoted, but at marginally reduced speeds. In practice the higher proportions of heavy goods vehicles are unlikely to coincide with such high flows.