Changes to legislation, together with special authorisation procedures, now enable local authorities to install a wide range of traffic calming measures at localities including villages on trunk and other major roads. In 1994, research began on the effectiveness of these measures on busy roads with a significant proportion of heavy goods vehicles. Thorney, on the A74 trunk road in Cambridgeshire, was one of two sites to be chosen initially for the study. The village speed limit is unchanged at 30mph; the measures include a gateway and chicane on each approach, with a part-time 20mph speed limit (past a school), a raised zebra crossing, a mini-roundabout, speed cameras, a refuge and kerb build-outs at adjacent build-outs at adjacent junctions in the village itself. `Before' and `after' measurements of vehicle speeds, journey times and traffic noise were carried out, followed by a public opinion survey and ground vibration monitoring. The results are presented in this report. Athough a number of measured speed reductions were substantial, most residents expressed reservations about the scheme. (A)
Samenvatting