Which streetscapes offer the most effective environmental protection
Every new technology has its downside. Texting has allowed us an easy way to meet, to stay in touch, and to ask our spouse to pick up milk on the way home. Yet the ease of texting has made it so appealing and ubiquitous that people are not putting their phones away before getting behind the wheel. Drivers distracted by texting are a recent but very large danger on the roads.
Texting and driving statistics, 2018
- Reading or sending texts takes a driver’s eyes off the road for 5 seconds.
- At 55 mph, this is the same as a driver crossing the length of a football field with eyes closed.
- 2.1% of drivers were spotted manipulating their cell phones while driving.
- This led to 60,000 phone related distracted driving crashes.
- More than half of these crashes resulted in injuries.
- 2,841 people died due to driver phone use.
- Cell phones as the cause of distracted driving is highest for those aged 16–39.
- Distracted driving (all causes) is responsible for 938,000 crashes every year.
Between 2014 and 2018, new laws and ad campaigns have caused a slight decrease in the incidence of crashes due to phones. Yet the percentage of drivers texting remains higher than all years before 2014.
Texting and driving – a closer look at the risks
In 2018, 2335 vehicle occupants died in car crashes because drivers were on their phones. 506 pedestrians, cyclists, and other bystanders were also killed by these distracted drivers. Environmental construction may not be able to secure against all such accidents. However, some standard traffic calming strategies, especially around problem areas, can make a big difference street safety.
Looking at the NHTSA’s Fatality and Injury Reporting System Tool (FIRST) gives clues as to where help is most needed. The data are different for rural areas and city areas and can give a sense of how density can affect fatalities. It is interesting to note that the number of rural fatal crashes is 92% of those in the city, even though 40% of Americans live in cities, and 40% more in suburbs. Higher rural speeds are a factor in crashes.
Data on fatal crashes involving distracted driving in 2018
Crashes at Intersections
- 19% of rural crashes happened at intersections (232/1234)
- 36% of urban crashes happened at intersections (479/1344)
Crashes on the Roadway
- 62% of rural crashes happened on the roadway (764/1234)
- 76% of urban crashes happened on the roadway (1022/1344)
Rural crashes are more likely to involve cars going off the road. Yet, 24% of fatal crashes in cities involve cars leaving roadway; it is still an issue, even at lower speeds. Intersections are more dangerous in the city. The density and variety of people using any given intersection increases the chances of there being a conflict.
Managing the risks of distracted driving in the city
Residential roads, and those around schools and parks, often have lower posted speed limits. Low speed gives drivers more reaction time to other street users. In residential areas, people don't always cross at controlled intersections, and may not expect cars to be passing. Children playing are also more unpredictable in these areas.
Texting removes all the advantages of the lower speed limit, by taking a driver’s eyes off the road and removing that extra reaction time. Additionally, the driver is more likely to miss the lower posted speed.
Creating an environment that requires slower speeds helps lower the impact of distracted driving. Consider:
- Trees along the route slow average speeds.
- Speed bumps and speed humps create a physical deterrent against speeding: where there is no curb, bollards may need to be added to prevent cars from driving around the obstacle.
- Chicanes, a curve of the curb into the road, narrowing the travel lanes, require both slower speeds and driver attention to navigate. These are often placed in an alternating series, requiring the driver to slalom through them.
Traffic calming around intersections is important in cities, where intersections hold conflict. Any stretch where drivers can get up to higher speeds needs excellent intersection design. Texting while navigating an intersection is especially dangerous. Some intersection design forces slower and more observant driving by design. Other design offers spaces of refuge to pedestrians.
Since drivers under the age of 40 are more likely to text and drive than older drivers, trouble areas near campuses often use these intersection calming strategies.
Intersection traffic calming includes:
- Roundabouts slow traffic and give those in the intersection right-of-way.
- Medians break up long stretches of crosswalk and provide pedestrian safety islands. This is especially important for people with slower-than-average speeds in crossing.
- Medians can also be used to limit the possible turning radius of cars. The less compact a car’s arc of turning, the faster it can move. Consider drivers who turn into the second lane rather than the curb lane.
- Curb extensions, also known as “Neckdowns,” narrow the road outlet at the intersection. When used well, these will cause vehicles to slow to pass through by limiting range of motion… even though widening the radius of the curb being turned around!
- Bollards along medians or curb extensions create both pedestrian security and a clear guiding visual line for drivers.
- Bollards linked with chains guide pedestrians to the safest point of crossing, like a zebra crossing or a light-controlled crosswalk. They discourage pedestrians from cutting unexpectedly through traffic.
- Pedestrian scrambles, no-right-on-red, and cycleway lights are all traffic light timing strategies that can lower the conflict between vehicles and other road users.
Security and crash-rated are most common bollards used for pedestrian zones. However, where tighter turning radiuses mean large vehicles are likely to run over median or main corners, Martello bollards both protect and help return vehicles to the roadway.
Managing the risks of distracted driving in rural locations
A lot of rural crash management is in the good design and construction of freeways. Designing safe roadways for above posted speeds is an essential element. Common elements include the following:
- Crash barriers between fast-moving opposing lanes.
- Bioswale medians or culverts to manage water runoff and prevent flooding.
- Careful, speed-matched road design such that both horizontal and vertical curves do not cause loss of control.
- Horizontal grades chosen to allow run-off but discourage roll-over.
- Well-posted speed and transition zone signs.
- Flashing lights ahead of large changes in speed near curves or climbs where taillights or traffic signals are impossible to see.
- Tactile paving to alert against lane drift.
More cyclists are doing long-haul biking. It’s increasingly important to create safe spaces for bikes along rural routes and freeways becomes increasingly important. Barrier separated lanes should be considered where roads are winding, narrow, or one lane only.
Managing distracted driving means building to prevent fatalities and injuries
Swedish traffic experts introduced the philosophy of Vision Zero in the late 90s. This design strategy suggests that lost human lives are not a reasonable trade for increased mobility. Both road and car engineering are required to put human lives first. In Sweden, this has meant extremely well implemented environmental design using many of the above suggestions. However, it has also meant changes to vehicles.
Fleet vehicles in Sweden have been equipped with breathalyzers, to ensure drivers are not on the road after drinking. These same alcohol locks are used on cars for problem drivers. Vehicle technology is a growing part of the safety landscape. Reminders for seatbelts and blind-spot alerts are familiar. Smart-vehicle systems that are already lowering fatality and injury rates. The chime to remind people to put on seat belts has been around for many years. Blind-spot alerts are a newer invention. Dash-cam technologies are now available to offer sleepy-driver alerts. These are currently a privately installed add-on which drivers install for backup. Perhaps similar face-scanning technology will someday alert distracted drivers to keep their eyes on the road.
Until that time, enforcement and awareness are important. Campaigns like Mothers Against Drunk Driving helped make a once common practice socially and culturally unacceptable. Current campaigns against distracted driving have slowed the rise of texting and driving, however, they have not reversed the trend entirely. A combination of cultural, legal, environmental, and technological advances together must bring texting and driving fatalities back down to zero.
- A Comprehensive Guide to Traffic Calming
- Bollards vs. Jersey Barriers
- Vehicle Crash Barriers
- Crash-Rated Bollards