Have you ever wondered what the safest times to drive are? How about whether crashes happen more often on rainy days or snowy ones, on local roads or main thoroughfares, on Mondays or Tuesdays, while the driver is talking on a cellphone or eating a sandwich?
The District Department of Transportation has the answers.
In a new report, completed in March and made available to The Post last week, Howard University researchers working for DDOT analyzed just about every aspect of the District’s traffic accidents from 2010 through 2012. We went through more than 150 charts, graphs and tables in the report to map the most dangerous intersections in the city and to find eight facts about when, where and how car crashes occur in D.C.
1. As the District’s population grows, car crashes are on the rise, too.
In 2012, the most recent year covered in the report, 18,428 crashes were reported — more than all but one year since 2001. Injuries, however, have stayed somewhat flat in recent years. Less than 30 percent of those crashes (5,258) led to injuries. Nineteen people died in car crashes in 2012, down from 25 in 2010 and 32 in 2011.
The average crash involved two vehicles. In total, 36,446 vehicles were involved in collisions in the District in 2012.
2. Drivers in D.C. suffer more injuries per mile traveled than those elsewhere in the country. But we’re also less likely to die on the road.
VMT in these charts stands for vehicle miles traveled. What these graphs say is that in the country as a whole, for every 100 million miles that cars traveled on American roads, 1.13 people died in 2012. In Washington, the rate was far lower, at 0.52. But driving in Washington caused injuries to 200 people for every 100 million miles traveled, compared to 80 people in the country as a whole.
This statistic is based on the fact that cars collectively drove 3.6 billion miles on streets in Washington over the course of the year. If we lined up all those cars and had them each drive straight, relay-style, they would circle the Earth more than 140,000 times. In just one year, cars drove far enough on Washington roads to get to Mars and back again — 12 times.
3. The calmest hours of weekdays are the most dangerous hours to drive on weekends.
It isn’t surprising that the wee hours of the night — when most of us are sleeping on weeknights, but the bars are just letting out on Saturdays — look drastically different on weekdays and weekends, from a traffic perspective. Take a look at the shapes of these two graphs, showing the hours that crashes occurred.
Overall, the highest number of crashes happened on Fridays, and the lowest on Sundays. Crashes varied from month to month, too: Seasonal patterns varied quite a bit over the three years of the study, but in general, accidents seemed to drop in the winter and pick up in the fall and spring.
4. Making left turns, backing up and changing lanes can all be dangerous. But by far the most crashes occurred when cars were simply driving straight ahead.
Almost 50 percent of the time, drivers were going straight when collisions occurred.
The most common type of crash was side-swiping, followed by rear-ending. About 10 percent of side-swipe crashes caused injuries, while rear-enders were often more severe. Thirty-eight percent resulted in injuries.
Even worse were head-on collisions — in almost half of 463 occurrences in 2012, someone got hurt. In three, someone died. Running off the road was the other type of vehicular accident most likely to cause injuries (87 times) and fatalities (three people, in two crashes) out of 197 instances.
The most fatal were crashes involving pedestrians. In the large subset of crashes examined in this table, cars hit people 805 times, causing injuries to 650 victims. Six people died.
5. The numbers are in: Men are worse drivers than women.
This goes way beyond refusing to stop for directions. Men were the drivers in about 65 percent of all crashes in the study. There’s no way to tell, for the sake of comparison, exactly how many men and women are on the roads in Washington. Drivers licensed in the District, Maryland and Virginia, as well other states, all use D.C. roadways. In the country as a whole, though, men and women hold driver’s licenses in roughly equal numbers, according to federal data.
Men were also responsible for far more alcohol- and drug-related crashes (263 men, 84 women in 2012) and speed-related collisions (386 men, 117 women).
6. Crashes involving walkers and bikers are on the rise.
The number of crashes involving pedestrians went up during each year of the study, from 777 in 2010 to 919 in 2012.
Bicycle crashes rose too. While the pedestrian crashes were split almost equally by gender and were distributed across the city, bicyclists involved in accidents were disproportionately male — roughly 77 percent, a figure that was consistent across all three years of the study. And of the 642 crashes involving bikes in 2012, only one happened east of the Anacostia.
7. Most crashes happen through no fault of the driver. But distractions are a big problem — and not just cell phones.
More than half the accidents in the study involved no road violations.
Driver inattention was the single most common contributing factor in all three years of the study. Cellphones, not surprisingly, were the most frequently identified distraction. Even using a hands-free mode wasn’t enough to forestall crashes. About one 1 in every 5 collisions linked to cellphones was caused by hands-free cellphone use.
Interacting with pets caused 11 crashes in 2012. And reading caused 22 — more than eating (13) and personal grooming (7) combined.
8. Speed kills.
Speeding caused just 3 percent of the crashes in the city in 2012. But 21 percent of traffic deaths were linked to speeding.