No matter how careful we are, humans make mistakes. We get distracted, misjudge distances, or don't always see everything around us. Even the most attentive drivers can't control everything on the road.

That's why the design of our roads and the speeds we travel matter so much. If we build more forgiving road environments, where a mistake doesn't automatically cost a life, we can protect everyone who uses our streets. Lower speeds are one of the most effective ways to do that.

Speed and survival

The relationship between speed and survival is stark. A person hit by a car travelling at 30km/h has a 90% chance of surviving. At 40km/h that drops to 60%. At 50km/h it drops to just 10%.

Lower speeds also mean drivers have more time to react and brake, reducing both the likelihood of a crash and the severity if one does occur.

It's not just about safety

Safer speeds create better neighbourhoods. When streets feel safe, more people choose to walk and ride. That means healthier, more connected communities, less congestion, cleaner air and more vibrant local streets. When streets don't feel safe, people avoid walking and riding, leading to more short car trips, more congestion and more pressure on parking.

Safer streets support independent travel for children, older adults and people with disability, giving everyone genuine choices about how they move.

Watch: Why 30km/h works

What we've learned from previous trials

In 2012 Stonnington introduced 40km/h streets in parts of Toorak and Prahran in the area bordered by Punt Road, Toorak Road, Williams Road and Dandenong Road. In 2016, 40km/h area speed zones were introduced to the residential precinct bordered by Williams Road, Orrong Road, Alexandra Avenue and Dandenong Road.

Council evaluated the impact and found overall crashes reduced since the new limit was introduced:

• total crashes reported by police fell from 70 to 38
• injuries fell from 137 to 79
• people walking or riding who were injured fell from 46 to 22.

The 40km/h speed limit in these areas has improved safety for everyone using our streets.

These results show what's possible when speeds are reduced. Research shows that dropping from 40km/h to 30km/h can deliver even greater safety benefits, particularly for people walking and riding, who remain most at risk even at 40km/h.

Read more at Safer Stonnington streets.