Road diet by Richard Drdul licensed under Creative Commons.

Ford pumped out a lot of cars in the early 1900s, and by the '60s there were so many vehicles on US roads that traffic engineers decided to add more lanes. Unfortunately, they were a bit overzealous, and many roads were expanded even when there was really no need. That left the country with a lot of overbuilt and unsafe roads that persist to this day.

Fortunately, there's a way to make these bloated roads safer with just some paint.

While it may seem counter-intuitive at first, reducing a street from four lanes to three with a middle lane for turns not only results in fewer crashes, but also speeds up traffic. That's because left-turning vehicles can simply pull out of traffic into the middle lane while they're waiting to turn, rather than stopping in the traffic flow and blocking the vehicles behind them. There are also fewer potential crash points.

Besides fewer lanes, reducing the width of the lanes also has a positive impact. Narrower lanes encourage drivers to slow down, which makes the crashes that do happen much less deadly. Plus, the extra space can be dedicated to cyclists, which makes the street safer for them too.

Of course, as with everything in life, context is everything. Road diets are more effective in certain areas than others, and there are a lot of factors at play. Check out the video to learn more!

Julie Strupp is Greater Greater Washington's Managing Editor. She's written for DCist, Washingtonian, the Wisconsin Center for Investigative Journalism, and others. You can usually find her sparring with her judo club, pedaling around the city, or hanging out on her Columbia Heights stoop.