General Road and Highway Discussion

[danbrotherston]

The conversation about visibility on the Cycling thread reminds me of an open question that comes up this time of year:

Why are there streetlights on highways?

There are obvious reasons for streetlights on city streets (pedestrians, cyclists, wayfinding)... but those reasons are all absent on highways (so long as the signs are lit or reflective). The recent widening of the parkway east of Fischer-Hallman was accompanied by the hoisting up of arrays of over-tall, over-powered light arrays that seemed to have absolutely no aesthetic consideration paid to them.

Ultimately I expect the answer is "Because the MTO says so in the HTA," but I'd like to know if there's a non-"because I said so" justification.

Because streetlights provide far better visibility than car headlights, it isn't just about signs and lines and other vehicles, its about situational awareness.

I suspect there are studies which show substantially reduced collision rates on busy highways with lighting vs. without, but I'm not actually aware of any so feel free to prove me wrong, but as a driver this is certainly my experience.  On a lit highway, I feel that I am more aware of my surroundings than on an unlit highway.