Roundabout math begs the question: why build risk?

whether human – A transportation project pitched as “corridor improvement” leans on familiar engineering language, while widely cited safety economics put a hard price on crashes. With American deaths in traffic tied to hundreds of billions in annual costs, the math of avoide

The traffic light changes, the queue doesn’t. For years, people have treated congestion and safety upgrades as separate problems—until the bill arrives in the form of crashes.

Every day, around 100 Americans are killed in car traffic. That’s 100 families who receive the devastating news that their loved one will never return home.

But there is another ledger, too—one that never shows up on a billboard. The National Safety Council estimates the total cost of motor vehicle deaths. injuries. and property damage is closing in on $500 billion per year. The Network of Employers for Traffic Safety reports that motor vehicle crash injuries on- and off-the-job cost employers $72.2 billion in 2018. their most recent study year.

For that same employers’ dataset, on-the-job crashes cost employers $26,081 per crash. The group also puts costs at $66,119 per million vehicle-miles of travel and $78,418 per injury. The numbers are eight years old. but the question they raise is immediate: if the costs are real. why do some road projects move forward as if they’re optional?.

A report-like quote inside the employer study spells out what’s behind the price tag: “Including insurance expenses. employer health care (medical) spending for motor vehicle crashes totaled $19 billion in 2018. Another $17 billion was spent on sick leave and life and disability insurance for crash victims. Protecting employees from motor vehicle crash injuries can be a valuable investment of time and resources.”.

The point isn’t to trade in human life like a commodity. It’s to insist that planners stop behaving as if fatalities and injuries belong to a separate world—one that doesn’t affect budgets, timelines, or decisions.

One figure used in federal safety economics is blunt by design. The US Department of Transportation says the value of a statistical life is roughly $10 million. while suggesting a range that includes high and low values. In that framework, every traffic fatality prevented through a traffic calming project is worth $10 million in economic benefits.

USDOT’s chief economist provides a methodology summary, and the numbers are an “order-of-magnitude starting point,” with the warning that precision shouldn’t be the focus.

Still, once you start running the calculations, the gap between rhetoric and planning becomes hard to ignore.

Consider what a county might advertise: a big road project using marketing phrases like “corridor improvement” and “signal upgrades.” The plan could lean toward a status quo fix—replacing a roundabout with a massive intersection featuring dual left-turn lanes. more through lanes. and other familiar elements.

The memory the public is left with can be simple: you’ve seen this movie before. And the safety math suggests the movie has consequences. One reason is timing and location. A third of traffic crash deaths happen at signalized intersections.

In a hypothetical comparison, USDOT reports that converting a signalized intersection to a roundabout can reduce fatal and injury crashes by 78%.

The next step is a scale check. The average number of fatalities and injuries at signalized intersections each year is around 7,500. That implies potentially over 5,800 lives saved or serious injuries prevented annually.

Now narrow it to the corridor a county might be selling. The hypothetical corridor’s cluster of signalized intersections accounts for 10 fatalities and 30 injuries in the last 10 years. Converting those signals to roundabouts could have saved 8 lives and 23 injuries.

The dollar figures follow the same logic USDOT’s valuation is built on. The hypothetical cost in the “status quo” scenario becomes $80,000,000 lost to fatalities and $1,803,614 lost to injuries.

Those totals are the kind of number a project manager would normally expect to see inside planning analysis—if the analysis is meant to compare options on the same footing.

So the tension arrives in the meeting, not the spreadsheet. If considering the value of human life leads to questions—“Are those costs part of the planning analysis?”—the project’s momentum depends on the answer.

If the response is that the cost of building a roundabout is too high—something like $1 million for each intersection, or even $3 million—the debate turns on whether prevention is treated as a benefit that belongs in the math.

On that point. the logic is straightforward: if “expensive intersections” prevent just one fatal crash. the DOT has already more than made up for the cost in economic benefits. according to the framework using the $10 million value of a statistical life. The calculations also leave out what cannot be easily priced: the pain and suffering carried by families of victims.

The larger argument underneath these numbers is less about roundabouts than about discipline. The writer says they’ve worked in the transportation planning and engineering industry since the 1990s and “rarely” seen the costs of deaths and injuries incorporated in benefit/cost analysis.

That mismatch—between what crashes cost and what projects account for—turns familiar engineering decisions into something else entirely: an unwillingness to treat prevention as a priority rather than a talking point.

The costs are not just a matter of safety studies. The best way to reduce crash-related costs is to prevent crashes, the piece argues, and prevention strategies are abundant. What’s described as rare is the willpower of decision-makers.

The prescription at the end is blunt too: make memes, make infographics, make videos; focus messaging from an employer’s point of view and from a local government point of view; share those materials with any politician who wants to be a hero.

Because when the numbers are this large, and the daily toll is this real, the real question isn’t whether safer options are possible. It’s whether the people holding the pen count the costs before the project gets past the drawing board.

traffic safety transportation planning road projects roundabouts signalized intersections USDOT value of statistical life benefit/cost analysis motor vehicle deaths employer traffic safety