Signing and Pavement-Marking Strategies for Multi-Lane Roundabouts: An Informal Investigation

Kinzel 2 Fig 1. " Standard " two-lane roundabout and key terms Abstract. Multi-lane roundabouts present motorists with a complex set of decisions. Unlike single-lane roundabouts, for which the only rule on entry is " yield to the driver on your left, then circulate to your right " , multi-lane roundabouts also require decisions about lane positioning – and these decisions are necessary at multiple points: entering, circulating and exiting. Many American motorists are not educated on the proper way to negotiate a multi-lane roundabout, and don't always know which lane is correct for making a given movement. As roundabouts have become more common in the United States over the past several years, resolving driver confusion has become an important task for the designer. An important question to answer, therefore, is: What design features can maximize clarity for motorists? Signing and pavement marking are perhaps the two most important tools designers can use to simplify driver understanding of multi-lane roundabouts. Jurisdictions across America and abroad have employed a variety of philosophies and approaches in signing and marking multi-lane roundabouts, ranging from minimal to elaborate treatments. This variation in practice, coupled with the relative lack of published guidance, provides evidence that the industry remains in an " experimental " phase and further standardization may be helpful. This paper examines and categorizes many of these signing and marking strategies. Arguments for and against the underlying design philosophies are presented, and general conclusions are drawn regarding the effectiveness of the various approaches. The paper also recommends future research, with an eye toward establishing reasonable and intuitive uniformity in signing and pavement-marking practice.