Does 70 mph cause more crashes?

RICHMOND, VA (WWBT) – Speed versus's a daily debate on Virginia's interstate highways, and for the past year and a half, drivers have enjoyed a new 70 mph speed limit on certain stretches of road. Elected leaders made a prediction at the time, and NBC12 put it to the test.

We wanted to know if the increased speed limit is causing more crashes on Virginia's interstates? What we found, may be surprising.

The sun was shining on that first day of July, 2010 - the day when 65 mph suddenly gave way to 70. Highway engineers and the lieutenant governor were there.

"We believe that it will help improve traffic safety," said Lieutenant Governor Bill Bolling on July 1, 2010.

More than a year and a half later, we wanted to know if that actually happened. Mena Lockwood is a VDOT assistant traffic engineer.

"Well, we're hoping that not much can go wrong," Mena said as our interview began.

NBC12 identified six segments of metro-area interstates where the speed limit was raised...on I-64, I-95, and I-295. We compared the speed-related crash numbers for one year before, and one year after the limit went up. The numbers are collected by State Police, and then analyzed by John Saunders, and his staff at the DMV.

"I don't believe that we had an expectation in this situation," Saunders said.

And that's good, because if John assumed, like we did, that there would be more crashes, it would've been wrong.

On I-64, between Short Pump and Charlottesville for example, speed related crashes had no change: 38 before, and 38 after. On the way out to Williamsburg, crash numbers went down 150 to 97...a drop of 35%.

They also went down on I-295 north of town (3 to 1), and on I-295 near RIC (18 to 14). Finally, on I-95...near Ashland: crashes were down a whopping 51% (168 to 82).

Sensing a potential trend?

"We're glad to see that the numbers have been going down," said Lockwood.

In fact, there was only one place where crash numbers went up. I-295 near the Tri-Cities: 75 crashes before the change, 83 now.

VDOT also discovered another surprising fact.

"People didn't jump, or increase their speed significantly just because the speed limit, they tend to drive what they feel comfortable," stated Lockwood.

So even if you prefer driving at or above 70, traffic experts say there's more to safety than speed.

"To slow down, to buckle up, to not drink and drive, to not drive distracted," Saunders said.

Other reasons for keeping the crashes down include better vehicles, education, and enforcement. However, both VDOT and the DMV stressed to us that there needs to be more scientific study before these numbers can be considered a true trend. That review is expected in 2013. 

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