Last Updated on November 13, 2015 by cassnetwork
The 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.
Though now rare in Indiana, they’re going to become far more common over the next few years, as INDOT mainstreams the MUT as a design option for reducing vehicle crashes and increasing traffic-carrying capacity on multi-lane highways.
By 2020, INDOT plans to build 12 more MUT intersections, in nearly every corner of the state,
with many other sites under consideration for similar treatment.
“MUT intersections have been used extensively in many other states,” said Damon Brown, Vincennes District Traffic Planning Engineer. “Research has shown that when used in proper locations, they are far safer and provide more capacity than traditional intersection designs.”
Brown continued “Initial public reaction to the MUT design is sometimes negative, but, like roundabouts, after drivers become familiar with the designs, they see the safety and value of them.”
Brown said one of the best features of a MUT intersection is that it minimizes the number of decisions that a driver has to make at a time. Instead of looking both directions for gaps in traffic before crossing a road, a MUT intersection allows drivers to focus on one direction at a time, to minimize mistakes.
Five additional MUT intersections are planned and funded for the Laporte District in 2016 – two will be built on US 24 in Cass County, two on US 31, one each in Fulton and Marshall Counties; and one on State Road 25 in Carroll County.
The US 24 and US 31 projects will be let in Fiscal Year 2019, while the State Road 25 project is slated to be let in Fiscal Year 2020.
There are three basic forms of a MUT: Restricted Crossing U-turn (RCUT), J-turn, and Boulevard Left. Each version of the intersection is unique but all feature U-turns after the primary intersection. Under the right traffic conditions, MUTS are proven to improve safety and reduce delay by separating and simplifying traffic movements.
MUTs improve the ability of traffic to cross a multi-lane 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 include traffic signals.
MUT intersections are designed to accommodate the wide turning radius of tractor-trailers and other large vehicles. Where road median width is not sufficient to accommodate larger vehicles, an additional pavement area is added. INDOT’s policy is to use alternative intersections where appropriate, including the Median U-turn, to support its ongoing commitment to improve safety and service delivery through innovation and cost-effective investments. MUTs increase safety by reducing by half or more the number of possible conflicts and the points where two vehicles cross paths. Most important,the conflict points eliminated are those most likely to produce severe injuries, notably right-angle or “T” crashes.
“Replacement of a conventional intersection with one of the MUT Forms has been shown to cut the frequency of severe crashes by up to 80 percent. MUT intersections also reduce intersection delay and overlay travel time when operating under the right traffic and road conditions. This improved capacity is achieved through more efficient traffic signal operation, including better phasing, timing and progression or coordination with adjacent intersections.”
More information about INDOT’s new MUT intersections is available at www.in.gov/indot/3392.htm