Background
TAC’s Canadian Roundabout Design Guide (CRDG) was published in 2017. Since then, new roundabout design guidance has been published in the United States (Guide for Roundabouts, NCHRP Research Report 1043, 2023) and the United Kingdom (Geometric Design of Roundabouts, CD 116, v2.1.0, 2023) – two jurisdictions whose experiences heavily influenced the development of the CRDG.
A 2023 survey found that 74% of TAC’s Geometric Design Committee members and CRDG purchasers saw the need for updated Canadian guidance; members of TAC’s Joint Roundabouts Subcommittee feel that updating the CRDG with a new edition would be more effective than one or more supplements.
Objectives
A second edition of TAC’s CRDG would draw from the new US and UK guides, address the topic of pedestrian and cyclist accommodation at roundabouts in detail (a primary interest of survey respondents), and offer guidance on other topics including accommodating large vehicles, constructing fastest paths, and turbo roundabouts.
The project tasks would include a literature review of other roundabout guides (particularly those published since 2017), a scoping workshop to identify and prioritize areas of new or amended content, and the creation of a second edition of the CRDG.
