Low Cost Safety Countermeasures for Improving Passing Opportunities in Congested Two Lane Two-Way Highways

Major operational problems associated with two lane two-way roads are speed differences between fast and slow moving vehicles and turning delays of vehicles. The unique operational characteristic of two lane highways is that overtaking is only possible when there is a gap in the opposing traffic lane. When the volume increases the passing demand increases rapidly while the gaps in the opposing traffic lane decline and thus reduce the passing capacity. The imbalance between passing opportunities and passing demand causes frustration among drivers leading to fatal crashes. This is considered to be a serious safety issue in congested two lane two-way highways. Low cost safety counter measures in congested two lane two-way highways have become effective and popular in many countries. Amongst them, passing lanes and climbing lanes play a major role. Application of different countermeasures is discussed. Some of the experiences and examples from New Zealand were elicited to describe the topic'.