This report provides a summary of the TRL trials, conducted between 1995 and 2000, which have attempted to combat the problem of 'swooping' at diverge areas. Two different approaches to solving this problem have been employed within this study; new lane separation markings including anti-swooping diamond shaped markings at junction 6 of the M6 motorway diverge and 'ghost' island diverge layouts. The trials have shown that reducing swooping manoeuvres during peak periods increases both the capacities of the mainline and of the slip road through the smoothing of vehicle flows through the section. The 'ghost' island diverge layout has been particularly successful in modifying diverging driver behaviour and has been used in both auxiliary lane and lane drop layouts. The study has also highlighted that for a scheme to be successful the modified layout should be accompanied by appropriate signing to inform drivers of the expected behaviour. The promotion of the scheme through local media prior to the installation, encourages regular users of the diverge to adapt their behaviour in order that the expected benefits can be experienced. (A)

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