Six speed changes in a kilometre: SA’s new 40km/h school zones spark confusion and steep fines

Drivers in South Australia are grappling with a rapid-fire series of speed limit changes as 40km/h school zones roll out across Adelaide, with some arterial roads shifting six times within a kilometre or less. The zones apply only during public school terms, which drivers are expected to know, and missing a single sign can attract severe penalties.

On Beach Road, south of Adelaide, one short section moves from 60km/h to 40, back to 60, down to 40 again, up to 60 and then 50, all while motorists contend with traffic lights and lane mergers. Similar patterns have appeared elsewhere, including on Main North Road outside Nailsworth Primary School.

The complexity has stirred anger and confusion among drivers. SA Police Commissioner Grant Stevens acknowledged the public’s frustration, saying the commentary around confusion cannot be ignored and that concern about how the new rules are applied needs to be recognised.

The Department for Infrastructure and Transport, however, noted that in eastern states where 40km/h school zones have existed for decades, drivers have become accustomed to them. Compounding the debate are South Australia’s penalties, which are the heaviest in the country.

Exceeding a signed limit by 20–29km/h — for example, by failing to slow to 40km/h on a 60km/h arterial — attracts a $955 fine, a $105 Victims of Crime levy and five demerit points. A 10–19km/h breach brings three demerit points, a $469 fine and the $105 levy. By comparison, in Victoria, exceeding the limit by 10–24km/h costs $407 and three demerit points.

In New South Wales, going over by 20km/h costs $592 and four demerits; by 10km/h it costs $345 and three demerits, with higher penalties applying in school zones (20km/h or more over costs $738). In Queensland, a 20–30km/h breach costs $751 and four demerits; 11–20km/h over costs $500 and three demerits.

Traffic lawyer Karen Stanley said road rules were originally designed to encourage decency on the roads but have become more complex alongside busier, distraction-heavy streets. She criticised what she called ambiguous and uncertain 40km/h signs, pointing to phrases such as “during school hours.” “That’s fine if you’ve got kids, but if you don’t, what does that mean?” she said.

With signs changing frequently, she argued, drivers are forced to hunt for speed limits instead of watching other cars. “It’s almost impossible to comply with every single road rule if you are having to look for signs that may appear without warning,” she said, adding she has sympathy for those fined in such circumstances.

Stanley also questioned the enforcement approach, saying on-the-spot stops by police can immediately influence behaviour, whereas camera-detected fines that arrive weeks later “does smack as a little bit of revenue raising” in her view. Only two of Adelaide’s new 40km/h zones feature illuminated flashing signs, and both are paired with permanent speed cameras that have issued nearly $700,000 in fines in just over one school term.

The illuminated signs are on Goodwood and Kensington roads. With the zones in effect only during public school terms and penalties among the nation’s steepest, the tension between safety goals, clear signage and enforcement methods is likely to remain a flashpoint for South Australian drivers.