Rose Hammond has persistently urged local authorities to reduce the speed limit of 55 mph on two-lane roads that run through her community, which includes supportive living spaces, churches, schools, and a busy park frequented by various youth sports leagues.
“What’s it going to take, will someone need to get hurt?” the 85-year-old criticized officials in northwestern Ohio, expressing frustration over the constant presence of motorcycles racing by.
With increasing community pressure, the local township in Sylvania requested a speed study from county engineers back in March to evaluate whether the posted speeds on Mitchau Road might be excessive. Their astonishing conclusion? Technically, 5 mph isn’t low enough.
This recommendation traces back to studies on rural roads conducted in the 1930s and 1940s, forming a significant basis for establishing speed limits across the U.S., even in urban settings.
From this research emerged the well-known 85% rule, which suggests that speed limits are determined based on the speed of the 15th fastest vehicle among 100 free-flowing vehicles, rounded to the nearest 5 mph increment.
However, some states are now rethinking this methodology while setting speed limits, especially with nudges from the federal government, suggesting changes are needed in how these speeds are determined.
The driver sets the speed
This principle operates on the assumption that the safest speed is the one that most vehicles are traveling. If drivers feel the limits are too low, they can simply accelerate and “vote with their feet.”
But this approach can create a problematic feedback loop, according to Jenny O’Connell, who directs the National City Transportation Association’s Member Program. “As people’s speeds increase, then speed limits tend to follow in response,” she explained.
The association has introduced an alternative to the 85% rule known as “city restrictions,” designed to lower risks for all road users by integrating factors like street activity and collision rates to set speed limits.
The report highlights that the 85% rule relies on outdated research, stating, “these historic roads are vastly different from today’s bustling streets.” With a rising trend in road fatalities nationwide, the federal highway administration recently clarified that the 85% rule is not an absolute rule and has been given too much weight when determining speed limits. Their updated guidelines encourage communities to consider road usage, pedestrian safety, and crash frequency.
Leah Shahum from Vision Zero Network, a nonprofit focused on street safety, hopes the manual amendments will further diminish the relevance of the 85% rule, admitting that changes are already influencing speed limit enforcement. Still, she noticed a resistance among some who prefer the simplicity of established practices.
“The 85th percentile shouldn’t be regarded as the ultimate authority, but it continues to be accepted repeatedly,” she noted.
Rethinking the need for speed
In a push for safer roads, Madison, Wisconsin, altered its speed limit to 20 mph in residential areas this summer through the “20 IS Plenty” campaign.
Seattle experienced significant success in a similar initiative seven years ago, achieving a notable reduction in serious accidents along with a 7% decrease in the speeds of the 85th percentile.
California has often leaned more heavily on the 85% rule than other states when determining speed limits. Yet, recent years have seen the loosening of restrictions at the local government level, allowing more flexibility in response to safety concerns. Advocates for pedestrian and cycling rights appreciate these changes but argue that more is needed.
Kendra Ramsey, the executive director of the California Bicycle Union, remarked, “There remains a strong belief that cars are the primary mode of transport, deserving priority and respect.”
Contrarily, Jay Beaver, from the National Driver Association, argues that adhering to the 85% rule is the safest way to regulate speed variations among compliant and non-compliant drivers.
“Ultimately, the specifics of what is on the sign are less important. The average driver will navigate based on the road’s nature. It’s unfair for the government to mandate a lower speed while designing the roads to encourage higher speeds,” he argued.
80 is the new 55
In the 1970s, fears over oil prices prompted Congress to impose a maximum speed limit of 55 mph, a law that was repealed in 1995, allowing states to raise it to 65 mph. Since then, speed limits have progressively climbed, with North Dakota recently becoming the ninth state to authorize an 80 mph limit. Texas has a segment that even allows for speeds of 85 mph between Austin and San Antonio.
While highways outside large cities have not been the focus of significant changes to the 85% rule, a 2019 survey associated with highway safety exposed some risks. Increasing a state’s maximum speed limit by just 5 mph correlated with a potential rise of 8.5% in accidents on interstates and 2.8% on other roads.
“I mean, you might have a different perspective when driving older cars, feeling the speed more intensely. Nowadays, at 80 mph, it doesn’t feel as fast in modern vehicles,” someone might quip.
An attempt to change the town
If elected officials in Sylvania, Ohio eventually yield to local concerns, the speed limit on Mitchau Road might see a significant reduction. The county engineers’ finding that, under the 85% rule, the speed limit should actually be raised to 60 mph has surprised some local leaders, although not the engineers themselves.
“Making informed decisions is tough without data to guide you,” commented Mike Pnievsky, an engineer in Lucas County.
For now, though, the speed limit stands unchanged. Ohio law dictates maximum speeds on 15 different road types, independent of what the 85% rule suggests.
Ohio’s guidelines are evolving to take context into account more significantly, making it possible for municipalities to lower speed limits if they can demonstrate a substantial pedestrian and cycling presence. Recently, consultants were brought in to assess potential changes, learning from practices in other states.
“The nation is slowly, and I mean slowly, moving away from the 85th percentile being the gold standard for decision-making,” remarked Michelle May, who oversees Ohio’s highway safety program. “People travel and live differently now than they did 40 years ago, and our focus needs to be on safety.”
Whether these changes will ultimately influence the speed limit on Mitchau Road remains uncertain. After years of unanswered calls and emails to state and local officials, Hammond shares her disappointment, saying, “I’m just so let down.”
