Median U-turns (2024)

A Median U-turn (MUT) is a type of intersection in which some left-turns or crossings from the mainline road or secondary crossroad are made using indirect, downstream U-turn movements. Intersections of this type are common and have performed successfully in other states, notably Georgia, Maryland, Michigan, Minnesota, Missouri, and North Carolina.

MUTs are a subset of design styles referred to as alternative, non-traditional, or innovative intersections, which also include roundabout, continuous green T, quadrant roadway, and displaced left intersections. While they differ in style, what these designs all share is a reduced number of conflicting traffic movements in comparison to traditional intersections, and that characteristic improves safety performance and lowers travel delay where certain traffic and site conditions are present.

There are three basic forms of a MUT intersection. Each is unique, but all feature U-turns after the primary intersection. They are a Restricted Crossing U-turn (RCUT), Reduced Conflict Intersection (RCI), and Boulevard Left.

Under the right traffic conditions, MUTs are proven to improve safety and reduce delay by separating and simplifying traffic movements. MUT intersections improve the ability of traffic to cross a multilane divided highway from a crossroad, and reduce the number of traffic signal phases, which frees up green time for more critical traffic movements through the primary intersection.

MUTs are generally limited to locations where the main road has four or more through lanes divided by a median. They may be used in rural or urban areas under high- or low-speed conditions and may or may not include traffic signals. They may be used individually or in a series along a corridor.

All MUT-style crossings include a companion U-turn location away from the primary intersection to complete what would ordinarily be a direct left-turn or direct through movement from the crossroad.

In June 2015, INDOT opened its first MUT intersection — a RCI — at U.S. 41 and State Road 114 in Newton County. By mid-2019, six more had been built. Others are planned where crash history, traffic volumes, and other road conditions justify the design.

INDOT’s policy is to use alternative intersections, including the Median U-turn, where appropriate to support its ongoing commitment to improve safety and service delivery through innovation and cost-effective investments.

The three different MUT-style intersections differ in how left turns or through movements are re-directed to the U-turn locations and whether crossroad traffic is controlled by traffic signals, stop signs, or yield signs.

With a RCUT, the main intersection is controlled with a signal and, in some cases, the U-turns are signal-controlled as well. A RCI has no traffic signal, only stop or yield signs. Apart from the presence or non-presence of traffic signals, thetwo forms look and function similarly and both typically permit direct left turns from the mainline. However, there is a RCI variation that does not permit direct mainline left turns. In both RCUT intersections and RCIs, crossroad traffic wanting to turn left or pass through makes an indirect U-turn movement. Through movements for mainline traffic and right turns are made the same way as in a conventional intersection.

The Boulevard Left intersection differs from a RCUT intersection or RCI in two ways: Direct left turns from the mainline are not permitted but occur beyond the primary intersection at the U-turn, and through movements from the crossroad are permitted. Boulevard Lefts go by different names across the country, including Michigan left and thru-turn.

Drivers approaching a Boulevard Left intersection from the crossroad make a left turn by first turning right, and then making a downstream U-turn. A variant of this intersection requires both the primary and secondary roads to travel through the primary intersection before making left turns at the downstream U-turns. In either case, all through and right-turn movements at a Boulevard Left are the same as a conventional intersection. With a Boulevard Left, traffic at the primary intersection is ordinarily controlled by a traffic signal, and U-turn locations may be controlled by yield signs, stop signs, or a signal in coordination with the main intersection.

MUT intersections significantly reduce the risk of severe crashes in certain traffic and road conditions. MUTs increase safety by reducing by half or more the number of possible conflicts and the points where two vehicle paths cross.

In a traditional intersection there are 42 different conflict points where an accident can occur. Of those, 24 conflict points can cause serious T-bone or right angle crashes – the crashes most responsible for fatalities and serious injuries at intersections. A MUT intersection can have no more than 29 possible conflict points and some MUT intersections can be designed so that there are zero crossing conflict points.