Dog bites man? Perhaps, but if you live in the bubble of traffic engineering you'd believe the opposite. Engineers continue, even after decades of evidence, to push the idea that making roads wider actually makes them safer. It's a mindset carried over from designing rural highways and interstates, where high-speed driving is in fact safer with wider lanes and broader shoulders. But in cities, the opposite is true. From the Economist of all places, writing about how few roadway deaths there are in Sweden:
LAST year 264 people died in road crashes in Sweden, a record low. Although the number of cars in circulation and the number of miles driven have both doubled since 1970, the number of road deaths has fallen by four-fifths during the same period. With only three of every 100,000 Swedes dying on the roads each year, compared with 5.5 per 100,000 across the European Union, 11.4 in America and 40 in the Dominican Republic, which has the world's deadliest traffic, Sweden’s roads have become the world’s safest.
What's the key? (Emphasis mine)
Planning has played the biggest part in reducing accidents. Roads in Sweden are built with safety prioritised over speed or convenience. Low urban speed-limits, pedestrian zones and barriers that separate cars from bikes and oncoming traffic have helped. Building 1,500 kilometres (900 miles) of "2+1" roads—where each lane of traffic takes turns to use a middle lane for overtaking—is reckoned to have saved around 145 lives over the first decade of Vision Zero. And 12,600 safer crossings, including pedestrian bridges and zebra-stripes flanked by flashing lights and protected with speed-bumps, are estimated to have halved the number of pedestrian deaths over the past five years. Strict policing has also helped: now less than 0.25% of drivers tested are over the alcohol limit. Road deaths of children under seven have plummeted—in 2012 only one was killed, compared with 58 in 1970.