There are several different types of Median U-Turns (MUTs) that INDOT uses. The MUT intersection design eliminates the cross-over between the four-lane divided highway. Here are the 4 major types of MUTs INDOT uses:
- Improved Safety
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.RCIs eliminate the need for motorists to cross the high-speed lanes of traffic to get to the opposing lanes. Nationwide, statistics show a more than 50% decline in crashes where RCIs are installed. Fatal crashes decline by as much as 85%.
- Recent Statistics
Since 2015, INDOT has installed seven RCIs at four-lane highway intersections in Indiana. These intersections have shown a substantial decrease in fatal and injury crashes since RCI installation.
INDOT has conducted performance analyses of crashes at each RCI, comparing pre-construction crash frequency and severity with post-construction data over similar time periods, ranging from 1½ to 5 years.
In overall effectiveness, INDOT’s analysis showed that the seven RCIs:
- Reduced fatal and injury crashes by an average of 81%.
- Reduced property-damage crashes by an average of 58%.
- Reduced crashes of any severity by an average of 68%.
INDOT’s analysis showed a dramatic reduction in fatal and injury vehicle crashes at each RCI:
- Fatal and injury crashes at each intersection declined between 64% and 100%.
- Property-damage crashes at each intersection ranged from No Change to 100% reduction.
- All crashes of any severity at each intersection declined between 38% and 100%.
INDOT continues to track the safety performance of these and future RCIs to assess their effectiveness and advance our understanding of the traffic levels, design, and site conditions most suitable for this highway feature.
- Improved Capacity
MUT intersections not only improve safety but reduce intersection delay and overall travel time when operating under the right traffic and road conditions. Although drivers have to travel slightly further to get where they want to go, using MUT intersections can require the same or less time than trying to wait for a safe and appropriate gap to cross traffic. For the RCUT and Boulevard Left, retrofitting a standard intersection will improve traffic capacity by 20% to 50%. This improved traffic capacity is achieved through more efficient traffic signal operation, including better phasing, timing, and progression or coordination with adjacent intersections. Stops are reduced by a third or more.
- MUT Advantages
When operating under the right traffic and field conditions, advantages of the MUT intersection over a standard intersection design include:
- Significant reduction in the risk of crashes due to a decrease in potential conflict points, particularly for angle crashes that tend to be severe.
- Increased capacity, reduced delay, and fewer stops overall. In some cases, there is even shorter travel time for traffic movements re-directed through the U-turn.
- Low cost in relation to conventional intersection construction or modernization and to other non-traditional intersection designs.
- Often can be retrofitted to an existing intersection without the need for additional land.
- Relatively straightforward to expand in the future, if necessary.
- A RCI may permit an existing traffic signal to be removed, or may delay the need for future signal control.