Study says higher speed limits may be safer

[US 89]

Article at https://www.sciencedaily.com/releases/2017/11/171117103757.htm, and also covered in KUTV and KSL.

New BYU research commissioned by the Federal Highway Administration (FHWA) shows a number of highway features that make accidents less likely. Among them are some that are intuitive: minimal hills and curves, paved right shoulders and concrete-barrier medians. But one finding was less expected: lower speed limits were associated with higher rates of accidents.

The FHWA seemed unsurprised by the finding, Heaton said, noting that lower speed limits were usually in high-traffic areas, which would increase the risk of crashes. But even controlled for traffic, the correlation held. Contrary to speculation about the dangers of high-speed-zone freeway sections, the finding shows "that we should really take a look at this a bit deeper and realize maybe higher speed limits aren't as big of a risk as we once thought," Heaton added.

In exploring Washington's hotspots that remained even after controlling for such variables, the BYU team found segments that likely had high levels of driver distraction. One such hotspot, on Washington's I-5, has a clear view of Seattle's Space Needle. Another was near a ski resort, which had, said Heaton, "lots of things to look at besides the road."

[slorydn1]

It actually does make sense. Contrary to what many believe, raising the speed limit doesn't get the fast drivers to drive faster-most of this crowd doesn't care what the limit is and are driving the speed they feel comfortable doing for the given road.

It does get the slow pokes and legal beagles to drive faster which causes the speed differential to be smaller.

The smaller the differential, the less likelyhood of having potential conflicts, which means less crashes.

[kalvado]

Another important thing here is that speed limit lost its function of relaying information about potential hazards ahead.
For that absolute speed limit is not that important, it is a difference between continuing 55(+20) MPH as opposed to 65-> 55 reduction: maybe there is something ahead that doesn't warrant +20 part?..

[dgolub]

Having a pervasive pattern of unnecessarily low speed limits that aren't enforced doesn't actually get people to go slower--it just causes them to view speed limits as a joke and ignore them.  It's easy to see how a speed limit of 65 MPH that's taken seriously could result in less speeding than a speed limit of 55 MPH that's viewed as a joke and leads to people actually going 70-75 MPH.  This is what happens on the Long Island Expressway (I-495) back where I grew up.