[blog] Stay alive and enjoy the ride: Imposing 20mph speed limits to protect lives – time for furious drivers to embrace reality

Sing it with me, folks...

You 👏 can't 👏 reduce 👏 the 👏 speed 👏 limit 👏 without 👏 also 👏 changing 👏 the 👏 street 👏 geometry! IT DOESN'T FUCKING WORK!

People don't give a shit about the what the speed limit sign says; they drive at the maximum speed at which they feel safe and comfortable based on the lane width, curve sharpness, etc. If you want to slow people down, you HAVE TO physically change the road -- narrow it, add chicanes, etc. -- to make it "feel" less safe. It's not fucking optional!

(Source: my background in traffic engineering.)

I think the main problem here is for folks forced to drive every day in the dervish of death that is rush hour.

If you can't afford to live near where you work (as is often the case in the UK), and you're already looking at a 1 hour commute both ways, current public transport isn't an option. You can either give up on sleep, or you will have to drive.

A lot of these changes are coming in the wrong order - first you improve public transport, create affordable housing near city centers, and drastically reduce the price (and let's be frank, increase the quality of) public transport, and THEN you hit car users to push them on to these options. In the current order, they just introduce further hardship to folks who already have a bad time.

Given that we know going over the speed limit raises your collision rate, meaning setting the speed limit so low every driver will go over it is genuinely dangerous, do we have any studies supporting the claim that reducing the speed limit reduces the collision rate overall? I couldn't find one, but it's a surprisingly challenging search - I easily found studies confirming that collision lethality scales with speed, but that's not my question.

Purely anecdotally, the vast majority of my collisions have been at very low speeds - in parking lots.

Tons of European cities already set-up speed-limit to 30 km/h. It's not just large cities, I've seen villaged limited at 30 too.
it's basically less nuisance for the residents

Fine where alternatives are available. But this also would slow down busses, right?

Why not figure out what distance it takes to get going say 30MPH and install speed bumps at those intervals? They hurt if you go over them to fast so its a disincentive to do so.

This is great, and with electric vehicles being more and more common it should be super easy to drive slow

One of the problems is that a lot of cars have trouble driving at that speed. It's really difficult to get them to remain at a constant speed under 25 mph or so, which can end up being extremely frustrating for the driver and encourages them to go faster than the speed limit. I realize this is a car design problem, but it's still a problem at present until that is fixed.