Case Study: Design of the Highway 406 Termination Roundabout

A multi-lane roundabout is currently under construction at the south end of Highway 406, the main highway connecting the cities of St. Catharines and Welland in southern Ontario. The southern section of Highway 406 is being expanded to a four-lane divided highway with grade-separated interchanges, and the roundabout will facilitate its termination at East Main Street in Welland. The use of roundabouts at highway terminations is common in countries where roundabout use is widespread, but rare in the United States and Canada. This paper describes development of the horizontal geometry of the roundabout, and some issues associated with the advance signing. During the conceptual design process decisions were made about the lane configuration of the roundabout, whether to shift the roundabout to avoid a nearby parking lot, whether to implement a southbound "semi" right-turn bypass ending in a yield condition or a fully-channelized bypass, and whether to construct an interim design for the roundabout or implement the ultimate design at the outset. During the preliminary design process decisions were made about the methodology by which large trucks would be accommodated, and the type, size and location of the advance signage associated with the roundabout. Overpass work along the two-lane section of Highway 406 commenced in 2010, and the widening of the highway commenced in 2011. Construction of the multi-lane roundabout began in late 2012. Completion of the entire project, under the jurisdiction of the Ministry of Transportation Ontario (MTO), is expected in the fall of 2013. (A) For the covering abstract of this conference see ITRD record number 201310RT334E.


  • English

Media Info

  • Pagination: 15 p.
  • Monograph Title: 2013 Conference and Exhibition of the Transportation Association of Canada - Transportation: Better - Faster - Safer

Subject/Index Terms

Filing Info

  • Accession Number: 01517954
  • Record Type: Publication
  • Source Agency: Transportation Association of Canada (TAC)
  • Files: ITRD, TAC
  • Created Date: Mar 11 2014 10:56AM