§ Mr. Greg KnightTo ask the Secretary of State for Transport, Local Government and the Regions if he will carry out an evaluation of the respective effectiveness and net cost of(a) road humps and (b) speed cameras as a means of reducing traffic speed levels. [49261]
§ Mr. JamiesonA review of traffic calming schemes in 20 mph zones undertaken by the Transport Research Laboratory in 1996 (TRL Report 215, "Review of Traffic Calming Schemes in 20 mph zones") showed an average vehicle speed reduction of 9.3 mph in the zones. A cost benefit analysis of speed and traffic light cameras, also published in 1996, showed that speeds were reduced by an average of 4.2 mph at camera sites.
Monitoring of the first year of a trial of the netting off funding system for safety cameras has shown average speeds at camera sites reducing by 5.6 mph. In the case of road humps they are usually incorporated with other measures in traffic calming schemes, so their net costs have not been separately evaluated. However, the value of the benefits exceed the costs by a factor of five to one in the case of speed safety cameras.
§ Mr. Greg KnightTo ask the Secretary of State for Transport, Local Government and the Regions what assessment he has made of levels of pollution and difference in noise levels as a result of road humps and traffic-calming measures which involve narrowing of the highway and the construction of an uneven road surface. [49260]
§ Mr. JamiesonA number of assessments have carried out examining changes in noise resulting from traffic calming measures, particularly resulting from different types of road hump. Results from these were published in Traffic Advisory Leaflets 6/96 "Traffic Calming: Traffic and Vehicle Noise" and 10/00 "Road humps: discomfort, noise and ground-borne vibration". Changes in vehicle 803W emissions and air quality relating to traffic calming measures have also been the subject of departmental research (see Traffic Advisory Leaflet 4/96 "Traffic Management and Emissions"), some of which is still on-going.