[bryanlarsen]

> safely

But is it? A 20/25mph speed limit implies a residential street. If you are doing 40 could you stop in time if a kid is hidden by parked cars and suddenly runs out into the street chasing a ball? If not, could you scrub off enough speed quickly enough to get below the ~20mph threshold where a collision with a pedestrian is unlikely to be fatal?

[tstrimple]

This is a function of the road design. We know based on studies that most folks drive the speed they feel comfortable regardless of the posted speed limits. I live right across the street from a school. It’s naturally a 25mph zone. But the roads are literally as wide as a highway road with perfect sight lines and bike lanes on both sides. It’s a very straight and wide path with clear visibility for about a mile so of course cars are going to fly down that road regardless of the posted limit.

All it would take is some traffic calming measures on each side of the school zone. Chicanes or bollards which narrow the road and force people to slow down and been demonstrated to be highly effective at regulating speed. Roads should be designed for the speeds that motorists are meant to travel if safety is an actual goal.

[bryanlarsen]

Yes, that illustrates my point. Road calming doesn't make the road less safe, but drivers slow down because it feels less safe. In other words, drivers don't have a great feel for what speed is actually safe.