§ Lord Reaasked Her Majesty's Government:
Whether they can provide information on average speeds or journey times on selected lengths of motorway in recent years.
§ The Parliamentary Under-Secretary of State, Department of Transport (Lord Brabazon of Tara)Surveys of average traffic speeds are conducted in the London area out to and including the M.25 motorway. These surveys measure the average rate of progress of traffic including time lost through congestion and delay at junctions.
Recent results are available from the 1983 and 1986 surveys. The average speed of traffic on the 162 miles of motorway standard road included in the surveys was 44 mph in the morning peak period, 56 mph in the daytime off-peak period and 54 mph in the evening peak period. This excludes the sections of M.25 motorway between Junctions 19 and 23 which were not open at the time of the surveys.
A detailed breakdown of the results is given in Department of Transport Statistics Bulletin (87) 37. A copy is in the Library. A new survey of the strategic London road network of trunk and designated roads is in progress, and results are expected to be published in March 1989.
Outside London, the department has carried out national speed surveys designed to measure the speed at which drivers choose to travel in unconstrained conditions, subject only to the legal maximum limit. Surveys have been conducted at selected sites on the road network every five years since 1977. The sites used include five motorway sites, and the surveys were only carried out when there was no traffic congestion at the site.
Results of these surveys have been published as statistical bulletins, the most recent being National Speed Survey 1987, Department of Transport Statistics (88) 30, which was published in January 1988. Copies of this bulletin are available in the House of Lords Library.
§ Lord Reaasked Her Majesty's Government:
Whether they can provide information on the average speed of surface traffic over selected routes in Greater London during working hours on weekdays as far back as records are available.
§ Lord Brabazon of TaraSystematic monitoring of average traffic speeds in London dates from 1968, when the Greater London Council introduced a programme to survey average traffic speeds on all London roads with flows in excess of 15,000 vehicles per day. The Department of Transport has continued the surveys since the abolition of the GLC.
Results since 1966 for different areas of London are published in Department of Transport Statistics 912WA Bulletin (87) 39, a copy of which is in the Library. Results for all survey network roads within London are shown below.
London average traffic speeds 1962–1986 (Weekdays) miles per hour Year Morning Peak Daytime Off-Peak Evening Peak 1968/70 18.1 21.3 18.6 1971/73 17.7 21.6 18.3 1974/76 17.9 21.7 18.3 1977/79 16.9 20.9 17.2 1980/82 17.5 20.6 18.0 1983/86 16.9 20.9 17.2 Some information for central London is also available from surveys conducted in earlier years, but it is not directly comparable with current data because of differences in method and coverage. I will write to the noble Lord with further details.