A split intersection is a rarely built at-grade variant of the diamond interchange. Compared to a conventional four-leg intersection or road crossing, the arterial road is split into separate carriageways by 200 to 300 feet (61 to 91 m), allowing a queue of left turning vehicles behind a completed turn into the crossroad without any conflict to oncoming traffic. On the crossroad, the four leg intersection is being replaced by two intersections. The beginning one-way traffic at the fourth leg makes the intersections reduce the number of conflicts similar to a three leg T-intersection to improve traffic flow.
- At Legacy Drive and Preston Parkway, Plano, Texas, with Texas U-turn lanes,
- At New Dallas Highway (US-77) and E. Industrial Boulevard TX-340 in Lacy Lakeview, Texas,
- At Stock Road and Winterfold Road in Perth, Australia
- It is the most common intersection design on Utah State Route 85, also called Mountain View Corridor, at begin of construction.
- At Sarcee Trail and Richmond Road, Calgary, Alberta, Canada,
Town center intersection
A town center intersection (TCI) is similar to a split intersection; however, both the arterial road and the crossroad are split into separated one-way streets. The resulting grid, most often implemented in a city, reduces conflicts to two directions per intersection.
The TCI's grade-separated variant is the three-level diamond interchange.
- Bared, Joe G. & Kaiser, Evangelos I. (June 2000). "Advantages of The Split Intersection". Public Roads. Vol. 63 no. 6. Federal Highway Administration.
- Bared, Joe & Kaiser, Evangelos (2000). "Benefits of Split Intersections". Journal of the Transportation Research Board. Vol. 1797. Transportation Research Board. pp. 34–41. doi:10.3141/1737-05.
- Rodegerdts, Lee A.; Nevers, Brandon; Robinson, Bruce; Ringert, John; Koonce, Peter; Bansen, Justin; Nguyen, Tina; McGill, John; Stewart, Del; Suggett, Jeff; Neuman, Tim; Antonucci, Nick; Hardy, Kelly & Courage, Ken (2004). "Chapter 10.3.1,". Signalized Intersections: Informational Guide. Federal Highway Administration. FHWA-HRT-04-091. (PDF)