Ask a Lincoln driver about the roundabout on 14th and Superior and you might hear about the trees. Or the sculpture. Or the shrubs planted in the center island that some drivers swear block the view and cause crash after crash.
City engineers say that's not what's actually going on. The real story, they say, is in the data, and it says more about how the intersection was originally built than what's growing in the middle of it.
From Lincoln’s oldest roundabout at 33rd Street and Sheridan Boulevard to a handful of newer restricted U-turns being built along rural highways, Nebraska transportation officials are betting on unconventional intersections to cut down on the state’s most severe crashes. The data, they say, backs them up. But changing how Nebraskans drive hasn't been simple, cheap or universally popular.
Roundabouts and traffic circles are often used interchangeably, but there are differences. Traffic circles, also called rotaries, are relatives of the modern roundabout. The first rotary in the United States was Columbus Circle in New York City, built in 1905 and designed by William Phelps Eno. The rotary design allowed vehicles to merge and drive at high speeds; vehicles entering the circle had the right of way. The design contributed to a high number of crashes and congestion, which led rotaries to fall out of popularity in the mid 1950s.
The first modern roundabout was created in the United Kingdom in 1966. The new design used smaller circles that forced traffic to slow down and gave the right of way to cars already in the circle.
The first roundabout in Nebraska was built in Lincoln in 2002, at the 33rd Street and Sheridan Boulevard intersection, and the city now has 72 of the roughly 250 statewide, the most of any city.
Roberto Partida, a transportation planner with Lincoln Transportation and Utilities, said one reason Lincoln has so many roundabouts is because they increase traffic safety.
"The data speaks for itself. Specifically, with 33rd and Sheridan, there has been a 73% reduction in crashes since that roundabout was installed,” Partida said. “And then more specifically, there's been an 80% reduction in injury crashes, which is really the focus of our Safe Streets Lincoln Vision Zero initiative."
One reason for that reduction is fewer conflict points. A traditional intersection has 32 potential conflict points; a roundabout has eight.
Wen Hu, a senior research transportation engineer with the Insurance Institute for Highway Safety, said the angle of a crash plays a big role in how severe it is.
"The most severe crash types at traditional intersections are right angle crashes, or the head-on crashes, left turn crashes. And all these crashes are almost unlikely at roundabouts because at roundabouts, all the vehicles, they travel in the same direction," Hu said. "So, they eliminate some of the most dangerous conflict types at intersections.”
The Federal Highway Administration found that converting a two-way, stop sign-controlled intersection to a roundabout produces an 82% reduction in fatal and injury crashes. Converting a signalized intersection to a roundabout creates a 78% reduction.
Omaha has seen the same trend.
The 63rd and Shirley Street intersection, once a two-way stop, averaged 3.5 crashes a year. After a mini roundabout was built in about two weeks, the crash rate dropped to 0.7 a year, a roughly 80% reduction. No fatal or injury crashes have been reported there since the roundabout was installed in August 2017.
The cost of each roundabout heavily depends on the project. The Nebraska Department of Transportation has built single-lane roundabouts for between $4 million and a little more than $7 million each, Neemann said.
“If the intersection’s staying open, or we can detour the whole thing, that has a lot of effect on what the cost is for that,” said Matt Neemann, state traffic engineer for the Nebraska Department of Transportation.
In Omaha, officials say roundabout costs are generally comparable to a traditional signalized intersection unless significant right of way is needed. The city’s modular, quick build roundabouts are its cheapest option at around $75,000; they sit on top of an existing intersection, typically take about two weeks to install and cost significantly less than a permanent roundabout.
Larger modular roundabouts, like one just outside Omaha in Ashland, cost around $1.4 million.
Lincoln officials look at the cost differently.
"Roundabouts are traditionally more expensive up front," said McClintock, a senior engineer with Lincoln Transportation and Utilities. "But when you look at the total life cycle cost of a roundabout versus a traditional signal, the roundabout does come out ahead."
Drivers navigate a roundabout using yield rules, not a signal, so it keeps working straight through a power outage that would otherwise leave a signalized intersection dark. A signal also has more parts that eventually fail and need repair or replacement, from burned-out signal bulbs to aging poles.
Designs can also shift depending on where a roundabout goes. NDOT builds its rural roundabouts larger to accommodate semi-trucks and other larger vehicles that aren't as common on city streets, Neemann said, though the underlying design components are the same everywhere.
Speed factors in too, rural roundabouts tend to have gentler curves that let drivers travel 30 to 35 miles per hour through them, while tighter urban curves slow traffic to 15 to 20 mph.
Roundabouts work best at intersections with a high number of accidents, heavy traffic delays or complex intersections with more than four roads. While roundabouts often need more space for the circle itself, they take up less space on the roads approaching them.
Cities also use smaller variations, traffic calming circles, which are small, raised circles built in residential intersections to slow down traffic, and mini roundabouts, which are smaller than a traditional roundabout, have one lane and are used at physically constrained intersections.
Cities implement Vision Zero Plans
Both Omaha and Lincoln have adopted Vision Zero plans. The Vision Zero Network, a national campaign, helps communities work toward eliminating all traffic fatalities and severe injuries.
"The Safe System approach prioritizes safety for people, focusing on designing roadways and vehicles and setting speeds and related policies in ways that ensure those inevitable mistakes do not result in severe injuries or fatalities," according to the Vision Zero Network website.
To be recognized as a Vision Zero city, a community must commit to eliminating traffic injuries and deaths by a specific date and lay out targeted steps for how it will get there through an action plan.
The Safe Streets Lincoln Vision Zero Action Plan was passed by the Ccity Council in March on a 7-0 vote. The plan aims to eliminate traffic fatalities and reduce serious injury accidents by 60% by 2045. Lincoln also received a $400,000 federal Safe Streets and Roads for All grant from the U.S. Department of Transportation, plus $100,000 in local matching funds, to help create the action plan.
"It looked at 10 years of crash data from 2014 through 2023. Then, from that crash data, we identified our high injury network. So where in Lincoln, what road segments, what intersections are we seeing a higher frequency of severe, injury type crashes," said Partida, who oversaw the plan. “And from there what type of strategies, what type of projects, what type of policy recommendations can we make to get us to our ultimate goal, which is all about eliminating fatalities and serious injuries on our streets."
One strategy in Lincoln's plan calls for a formal roundabout first policy. States including New York and Virgina have adopted similar policies, making roundabouts the preferred option for new or rebuilt intersections, subject to an engineering analysis to confirm one is feasible.
"Just the fact that we have that in our action plan, I think speaks to our approach to how we design intersections and view traffic safety in general for the city," Partida said.
Omaha implemented their Vision Zero plan in November 2023, with a goal of zero fatalities and serios injuries by 2045. The city built its Vision Zero Action Plan aimed at including community input and creating actionable and measurable strategies.
Jeff Sobczyk, Omaha's Vision Zero Coordinator, said Omaha's modular roundabouts give the city a low-risk way to test whether a roundabout will work at a given intersection before committing to a permanent one.
"We've been pleasantly surprised that the community has been relatively supportive of this, because in general, the city is not really keen on roundabouts for various reasons. So, I think a way to really break down that negative view towards roundabouts is you get them out there, you put your quick builds out there as quick as possible knowing that if it doesn't work, you can remove it," Sobczyk said. "So that's one reason why we like that, its adaptability, but also the low cost that it has. Focusing on those opportunities for those low-cost, high-impact projects, which are anything really modular, is what we're trying to pursue."
One way Lincoln and Omaha have been trying to cut down on community confusion is through educational campaigns. Partida and others have staffed a trivia-style booth at Big Red Welcome for incoming University of Nebraska-Lincoln freshmen, quizzing them on how to yield when entering a roundabout.
"That just in itself starts those conversations, and it's a good opportunity to educate our new fresh blood that is starting to drive our streets," Partida said. "And then any time we have different types of community engagement events, these are always opportunities for us within the city to kind of have those conversations around, traffic safety in general, but roundabouts, of course.
Sobczyk said most of the exposure to Omaha's Vision Zero plan comes through other community events.
"We are at a lot of pop-up events. We have a lot of safety specific studies that are going on that are driven by vision zero. So, when we're out, talking about that project, we talk about Vision Zero," Sobczyk said. "Early on we specifically went out and just had vision zero tables and talked to the community about their concerns about safety on our transportation system."
Nebraska tests a new form of traffic control
Another form of traffic control the Nebraska Department of Transportation is implementing is newer to Nebraska.
A reduced conflict intersection, also known as an RCUT or J-turn intersection, can be a confusing concept for drivers the first time they come upon one. To use an RCUT, a driver turns right onto a divided highway when traffic allows, then merges into the left lane. From there, drivers can make a U-turn and continue in the opposite direction. The design keeps drivers from crossing multiple lanes of traffic, which can lead to a crash.
"Really, these are the things that make these as successful as they are, reducing the angle of crashes if they happen, and reducing the number of conflict points that exist there,” Neeman said.
Nebraska's first RCUT was installed in 2020 near the small Platte County city of Humphrey, at U.S. 81 and Nebraska 91. Between 2021 and 2023, the RCUT reduced crashes there by 54% and reduced fatalities and injuries by 96%. RCUT intersections let drivers focus on one direction of traffic at a time.
The state has built two more RCUTs, near Murray and North Bend, and has a fourth under construction near Palmyra.
RCUTs conflict points, any point within an intersection where road users may potentially collide. A typical four-lane highway has 42 conflict points, but RCUTs only have 24, and accidents at RCUTs tend to be less severe than crashes at traditional intersections. Crossing conflict points, where vehicles move in opposite directions, tend to produce the most severe crashes, often right angle or T-bone collisions. RCUTs reduce those high-risk crossing points and lower the odds of a severe accident.
RCUTs for now are exclusively a rural tool in Nebraska. All four of the states' RCUTs are outside city limits, partially because the design needs more right of way than tightly spaced urban intersections usually have, Neemann said.
States with more RCUT experience, like Missouri and Minnesota, have mostly kept them in rural and suburban corridors for the same reason.
NDOT educates drivers
Similar to what Omaha and Lincoln do for roundabouts, NDOT runs an educational effort for RCUTs, aimed at younger drivers. The department’s public involvement team visits schools and communities near newly built RCUTs to walk students through how the intersections work before they're out on the road on their own.
"We've gone to the schools that have been in the locations where they have been built, talked to the kids who are about to get their learner's permits, about to get their driver's licenses, talk to them about how they operate and what they need to do when they go through them," Neemann said.
NDOT will send someone to a school on request to answer questions about how to navigate an RCUT.
“I think as more and more roundabouts are built and these engineers have more experience, and there are more mature design guidelines for building roundabouts. Generally the public will become very acceptable of roundabouts,” Hu said.
For now, Nebraska’s transportation officials are betting that changing how people drive can save lives, one merge, U-turn and roundabout at a time.