Road humps near a structure in a 20mph limit

Fri, 8 Nov 2024 12:27:41 GMT

The Road Humps Regs 1999 stipulate that no road hump shall be located within 25m of a culvert (as well as other structures) unless the road hump is within a "20mph Zone" (signed with Diag 674, not Diag 670), the assumption being that low traffic speed induced by traffic calming will unlikely damage the structure.

Since the 1999 Road Hump Regs, the TSRGD has relaxed the requirements of what constitutes a "20mph Zone" which originally required physical "traffic calming features" no more than 100m apart. "Traffic calming features" now include 20mph repeater signs, so the difference between a 20mph "limit" and a 20mph "Zone" has become negligible.

If a highway authority is satisfied that a hump would not cause damage to a structure, the decision whether to install it boils down to a technical signing issue.

Has anyone overcome this issue aside from simply not constructing the hump? Sought permission? Stuck up the requisite "20mph Zone" signs?

Fri, 15 Nov 2024 17:05:54 GMT

I would think it a perfectly reasonable interpretation to say that any 20 mph limit is equivalent to a 20mph zone. One could argue that 20 mph limits were rare and therefore not considered by the authors of that SI in 1999. However, a very strict reading might say the opposite.

A similar issue has arisen in Wales, where 20 mph Zone signs have been removed in areas that are 20 mph by virtue of their street lighting. Do the road humps that remain now need warning signs for them? Some authorities say yes they do, so Welsh Government has prescribed some specific warning signs for "Traffic calmed area" to address this.