No, silly— “RCUT” refers to an alternative intersection, also known as a superstreet, J-turn, or restricted crossing U-turn. An RCUT works by redirecting side street approaches—including left-turn and through movements—by requiring drivers to turn right onto the main road and then make a U-turn maneuver at a one-way median opening 400 to 1000 feet downstream. With this design, the conflicts that can lead to far-side angle crashes are eliminated. Field experience shows that properly designed RCUTs can reduce fatal and injury crashes by 70-80%.
One of the best places to implement an RCUT is a multi-lane freeway with a minor roadway intersection and limited access right-of-way. The primary and U-Turn intersections within an RCUT can be signalized or unsignalized depending on the intersection traffic volumes and signal warrants.
While an RCUT intersection can be very beneficial, it is not the right choice for every intersection. Weighing the pros and cons is vital in making an informed decision. Below is a list of advantages and disadvantages that come with using an RCUT.
- Greater vehicle efficiency for the through movement on an arterial in a signalized corridor, and reduced opportunity for crashes compared to conventional designs.
- Improved progression.
- Conflict points are reduced from 42 to 18 or 24 depending on whether or not the mainline left turn movements have been restricted.
- 30% reduction in crash rate and up to 50% reduction on crash severity.
- Enhanced opportunity for two-phase signals, short cycles, and the chance for good progression in both directions of the arterial at any speed and signal spacing.
- Better service to through travelers on the major arterial in urban and suburban settings.
- Works well with angled side roads if the angle is not advantageous for left turn movements
- Not an optimum design choice if the minor street through or left-turn movements are similar to mainline movements, because the design favors the mainline movements by providing more throughput capacity.
- Potentially higher construction cost than a conventional design.
- May have higher maintenance cost.
- Creates longer crossing distances that require longer pedestrian crossing times.
- Increased signing and pavement marking requirements to provide clear and timely information.
What does an RCUT need?
Median width is a crucial design element when considering an RCUT. These intersections typically require minimum widths between 47 to 71 feet. With a right-of-way width of 140 to 165 feet typically. Right-of-way requirements can be reduced by using bulb-outs or loons or the use of a reverse curve on the main street through movement.
While the cost of an RCUT is more than double the cost of a traditional intersection, it is much less than a freeway alternative. I have found that when there is ample right-of-way width and additional intersection capacity requirements—such as dual lefts, three through lanes, and double rights on all legs of the intersection—and the side street volumes are lower than mainline, then an RCUT will provide improved levels of service over traditional designs. An RCUT should also be considered when an overpass is recommended to provide improved levels of service. In this scenario, an RCUT can bring construction cost savings.
We have seen specific, real-world benefits from RCUTS in use today. However, based on DOT surveys, only 43% of US states currently use RCUTS. Of the states that do, 20% have only 1 to 5 RCUTS. Georgia and Wisconsin have more than 26-50 RCUTs in operation, and North Carolina has more than 50. We have seen that wait time on the minor approach at an unsignalized superstreet intersection is half the wait time at a conventional intersection when using RCUTS. In addition, crashes are reduced by 21-59% at unsignalized RCUTs, and fatal/injury crashes are reduced between 50-100%, according to six state studies occurring between 2012 and 2018.
Overall, RCUTs can bring numerous benefits and enhance the safety of our roadways and communities. While they are not always a viable option, considering an RCUT as an alternative to traditional intersections can result in significant cost savings, enhance efficiency, and create safer roadways for motorists and pedestrians alike.