J-Turns

What are J-Turns?

The J-turn is an alternative to traditional roadway intersections on a four-lane highway. Instead of motorists crossing fast-moving lanes of traffic to get to the opposing lanes, drivers at a J-turn intersection turn right in the same direction of traffic, merge into the left lane, and then make a u-turn in the direction they intend to travel. Although drivers will have to travel slightly further to get where they want to go, using J-turns can take the same or less time than trying to wait for a safe and appropriate gap to cross traffic.

The point of a J-Turns is to greatly reduce - or even eliminate - a significant number of severe crashes common when drivers must cross-over busy highways to reach another road.

In the J-turn design drivers turn right in the same direction of traffic, and merge safely into the left lane to prepare to make a left turn in the direction they intended to travel. This option uses an extended deceleration lane, basically adding a third lane on the highway to allow traffic making a left turn onto opposing lanes to safely pull off the main line, out of the way of high-speed traffic. Also, acceleration lanes may be constructed to allow traffic an opportunity to gain speed after turning onto the highway.

How do J-turns enhance safety?

J-turns have proven to be a safer alternative to a traditional roadway intersection on a four-lane highway because they eliminate or substantially reduce right-angle crashes, the crash the most responsible for fatalities and serious injuries at intersections. In fact, the installation of J-turns at similar intersections throughout Indiana and the nation have shown a substantial decrease in fatal and serious injury crashes.

J-turns eliminate the need for motorists to cross the high-speed lanes of traffic to get to the opposing lanes. Studies done by the National Cooperative Highway Research Program show J-turns provide a significant reduction in right-angle, “far” side crashes.

In a traditional intersection there are 42 different conflict points where an accident can occur. 24 of those 42 conflict points can cause serious accidents such as t-bone or right angle crashes. A J-Turn intersection can have no more than 29 possible conflict points and some J-Turn intersections can be designed so that there are zero crossing conflict points.

How do you drive a J-Turn?

 

 

The J-turn eliminates the cross-over between the four-lane divided highway. In the J-turn design, drivers turn right in the same direction of traffic and merge safely into the left lane to prepare to make a left turn in the direction they intended to travel. This option uses an extended deceleration lane, basically adding a third lane on the highway to allow motorists making a left turn onto opposing lanes to safely pull off the main line, out of the way of high-speed traffic.  

Recent statistics about J-turns:

Nationwide, statistics show a more than 50 percent decline in crashes where J-turns are installed. Fatal crashes decline by as much as 85 percent.

In June 2015, INDOT opened its first J-turn intersection at U.S. 41 and State Road 114 in Northwest Indiana. From 2008-2015, the intersection averaged four crashes a year, almost 40% of those were injury crashes, including one fatality. In the first year of operation for the J-turn, the intersection experienced one minor crash, and no injuries or fatalities.

In 2011, INDOT widened U.S. 231 in Spencer County to four lanes, and for the first three years, there were at least four deaths and nine injuries at the intersections with S.R. 62 and S.R. 68. Since the intersections were converted to J-turns in the summer of 2016, no serious injuries or fatalities have occurred at either location.

How can I learn more?