Narrow Streets: Safer for Cities?

Reassessing Street Design: Johns Hopkins Study Impacts Civil Engineers

A examination conducted by the Johns Hopkins Bloomberg School of Public Health has prompted us to reevaluate our outlook on roads. This investigation has shattered the notion that bigger lanes are more secure, since when there is additional space for errors, it can result in fewer incidents.

Whilst automobiles are becoming more and more reliable, findings from the inquiry showed that roads with limited lane widths plus applicable speed limits led to greater safety than highways boasting broader lanes.

Traffic fatalities remain the primary cause of death for individuals aged one to fifty-four in America. The level of fatalities from transportation related accidents also ends up overtaking other fully developed nations, with 11.6 deaths per 100,000 contrasted against figures of 1.3 and 3.2 coming out of Europe. Furthermore, recently conducted research by the Insurance Institute for Highway Safety has found that vehicles such as America’s number one selling Ford F-150, with sharper front design, are very risky to other drivers on the street.

Narrow Lanes Save Lives

Initially, 7,670 sections of roadways located in seven different US cities were included in this research, yet it subsequently became confined to 1,117 arbitrarily chosen lanes that offered comparable characteristics. In terms of understanding the nexus between 20 constitutive elements of street design and various security measurements, the scientists made use of the collisions going on in each lane from 2017 up until 2019. The amassed information displayed that, despite the breadth of the lanes ranging from nine, ten, to eleven feet, there was no divergence in the number of crashes.

However, 12-foot wide lanes caused a significant hike in accidents as compared to narrower route thoroughfares.

“Our research on city lane widths has revealed a counterintuitive result – that wider lanes in urban areas can actually lead to more crashes and fatalities,” declared Shima Hamidi, PhD, director of the Center for Climate-Smart Transportation at the Bloomberg School. “We must ask ourselves: is it possible to narrow lanes without compromising safety, and if so, how can we best utilize the extra space in existing infrastructure? These are the questions we seek to answer.”

The investigators further concentrated on velocity restrictions along those roads. Examining the case where two lanes were made, at speed of twenty to thirty-five miles per hour (mph) and with a distance of nine to twelve feet, revealed no change in security. However, the danger intensifies if these rates are augmented to 30 to 35 mph on streets having a width of 9-12 feet.

Experts concluded that roads with wider lanes and higher speed limits are 1.5 times more prone to collisions, thus substantiating that these streets do not become safer even though authorities emphasize on creating automobiles secure for pedestrians.

Despite concerns of congested roadways, Hamidi has articulated that permitting fewer lanes is able to constrain speed and not boost it. Diminishing these avenues can improve the shift to other types of transport, such as cycling and walking, thus assisting in the decrease of greenhouse gas contaminations.

“Narrowing the lanes of a street may be the most effective way to slow traffic in areas that are unable to install speed control devices, and even those that can,” stated Jonathan Larsen, Transportation Division Director for Salt Lake City Corporation. “This is the best form of traffic calming for these particular streets.”