Australia’s target of net-zero emissions by 2050 gets a lot of attention, but in 2021 every level of government in Australia came together to agree on another ambitious zero target – zero road deaths by 2050.
Australia’s National Road Safety Strategy 2021-30 is aligned to this vision, aiming to halve road deaths by 2030. But there’s a big problem – instead of steadily shrinking, deaths on Australian roads are at their highest level in 12 years.
The rapid spike over the past four years also represents the fastest growth in road deaths since the 1960s, before seatbelts were made mandatory.
Amid this, a new discussion paper from Engineers Australia’s Transport Australia Society (TAS) is pushing for a rethink of urban street design.
Emmerson Richardson, co-author and past chairman of Engineers Australia’s National Committee on Transport, said the Towards Safer and More Liveable Urban Streets discussion paper followed ongoing work from TAS to highlight and move beyond the shortcomings in traditional street design.
“For many decades, the planning and design of urban streets has been guided by Austroads design manuals that are based on the movement of cars and trucks,” he said. “Little or no advice is provided on how street design could be used to lower speed as a means of improving safety.”
Failing to take into account the needs of other street users such as pedestrians and cyclists early enough in the process, Richardson said, often means it is too late to effectively address their safety at a reasonable cost.
“When we improve safety, we also improve connectivity and liveability for everyone,” he said.
Richardson said it was well known that reducing driver speeds reduces crashes, injuries and fatalities on urban streets.
“If a child in a local street steps out in front of a car travelling at 30 km/h that is 20 m away, the average driver would be able to stop before reaching the child.
“But if everything else in that scenario is the same and the car is travelling at 50 km/h, the car might still be travelling at 50 km/h when it hits the child. Given a reaction time of 1.5 seconds, the vehicle would travel an estimated 21 m before the driver applied the brakes.”
Partially because of this, the road-safety risk for pedestrians and other vulnerable road users does not increase linearly as the speed of vehicle traffic increases.
This factor has driven a global surge of interest in reducing urban speed limits below where they have often sat for decades.
“For instance, there has been a lot of work done in Wales, where the default speed limit is now 20 mph (30 km/h), unless it can be demonstrated that it is safe to go with a higher speed limit.”
Some councils in Australia, including in inner-city Melbourne, are also trialling these speeds.
Recommendation 1: Rethink speed limits
Richardson said reliance on legislation and signs to reduce speed has only a small impact and, on its own, it does not achieve the speed reduction required.
“The physical environment of a street must be changed, in conjunction with a reduced speed limit, to maximise both speed and crash reduction. The discussion paper is saying that we need to take a different approach to speed management because we have reached our limits in obtaining benefits from current practices,” he said.
“We want to have a way of controlling speed that doesn’t feel anti-car or putting drivers at a disadvantage. Currently, streets can have very different speed limits but not look much different in design or appearance.
“Drivers should be able to know the appropriate speed of a street without relying on a sign.”
As the discussion paper points out, many urban areas feature speed limits of anywhere from 30-80 km/h, in 10 km/h increments, often with no perceptible change in the street environment.
“The current system of six different urban speed limits [has drivers] mostly dependent on speed limit signs placed infrequently along the roadside. It is not surprising that instances of speeding are commonplace,” it states.
One of the foundational ideas of the discussion paper is adopting a three-tier speed framework for urban streets, with only three speed limits – 30, 50 and 70 km/h – each with a distinct appearance and design. This would give drivers a clear understanding of the design speed of the street.
This approach is common in both the UK and much of Europe.
Recommendation 2: Reduce lane widths
Under the current Austroads guidelines and those of most state road authorities, the default lane width on urban streets is 3.5 m.
“Conventional wisdom has said it’s safer because there’s more room for a vehicle to manoeuvre within that lane and perhaps move sideways a little bit to avoid someone within the lane, and that is true,” Richardson said.
“But what making the lanes wider also does is send a signal to drivers that it’s more comfortable for them to drive faster. So they do drive faster and this puts pedestrians and other vulnerable street users in more danger, more than negating any safety benefit from wider lanes.“
Richardson said a major national study in the USA by the Johns Hopkins School of Public Health, found no evidence that wider lanes are safer and in some instances are less safe. Since 2010, the UK has made 3 m the default lane width for urban streets.
The discussion paper recommends following suit, setting the default lane width for urban streets with speed limits of 50 km/h and under at 3 m.
“By making narrower lanes, you also create space for providing things like wider verges and plantings, or central medians to make it easier for people to cross,” Richardson said.
Recommendation 3: Convert four lanes to two
Richardson said that in recent decades, countless localities have invested in widening existing two-lane streets into four-lane undivided roads in order to increase capacity.
“Daily traffic volumes along many of these streets have remained relatively low, often below 20,000 vehicles a day, because the traffic flow is constrained by intersection capacity along the route,” the discussion paper states. “The opportunity exists to convert many of these streets back to one lane each way, which is more in keeping with an urban street, without much or any loss of capacity.
“In a few cases, where high traffic volumes exist, it may be considered desirable to reclassify the street as a major traffic route and upgrade it to dual-carriageway standard with a 70 km/h speed limit.”
Richardson said reclaiming these lanes would deliver space for purposes that would benefit other road users, such as median crossings, greenery, more parking or bike lanes.
Recommendation 4: Make crossings safer
Richardson said that while much effort has been put into creating a comprehensive, unbroken network of streets for the efficient movement of vehicles, other street users such as pedestrians and cyclists face a fractured patchwork of connections, often facing no safe way to reach their destination.
“Pedestrians suffer longer routes than necessary and find it difficult to safely cross streets carrying significant volumes of traffic at speeds that are well above the safe system speed for pedestrians – 30 km/h,” he said.
To aid pedestrian crossing and connectivity, the discussion paper suggests a suite of improvements, including more widespread use of pedestrian refuges and zebra crossings, particularly those with a raised walkway, also known as wombat crossings.
Such crossings are particularly needed on roundabouts, where under current law drivers have right of way if no crossing is present.
“There are roundabouts on busy pedestrian routes that pedestrians just can’t cross safely,” he said. “Zebra crossings, like roundabouts, are safest at traffic speeds of no more than 30 km/h.
“Traffic speed should be controlled through the roundabout design by installation of a wombat crossing, by humps or horizontal traffic calming devices on approach to the roundabout, or by a combination of these measures.”
Another recommendation the paper makes is making turns at many urban intersections tighter, to reduce crossing distances for pedestrians and the speed of turning traffic.
The large radius of many intersections cater to large vehicles such as garbage trucks, but the discussion paper argues that the low traffic volumes and speeds in urban streets mean that the few large vehicles can use part of the opposing lanes without undue conflict to other street users.
“There are many streets in older areas of our cities where this occurs, and results in minimum disruption,” it states.
What happens next
Richardson said the end goal of this project is to see the major road authorities rethink their design guidelines to take a more holistic approach, looking beyond design for cars and trucks to prioritise equitable use by all street users.
He said while some of the recommendations seem ambitious, they all have proven track records in other jurisdictions and are mainly low-cost solutions.
“My strong view is that if we take this sort of engineering approach to street design, we will be able to demonstrate safety outcomes from drivers adopting a less aggressive approach that benefits everyone, but particularly vulnerable street users, including children, people with disabilities and the elderly.
“Most councils are reactive to what people tell them and we’re starting to see more and more concern about both safety and liveability. There is a community of support for these changes.”
Emmerson Richardson will be joining Prue Oswin MIEAust CPEng to host a webinar on this discussion paper on March 27. To learn more, visit the event page.
Thanks for the great work presented by Mr. Emmerson Richardson. Engineers Australia needs to encourage more engineers to get involved to achieve the common goal of zero road deaths by 2050.
pavement use red brick tiles , right, common in hk. use the tiles with rought surface, prevent slipery
road way not use this, not enough strength to stand vehical load. may crack, use concrete with reinforcement, put on top bitumin layer, to prevent rain water seep in , wash away soil, vacuum, road collapse
I wonder how many of road fatalities occurred on urban streets. I have not seen data on road fatalities for some time but in the past most fatalities occurred outside urban areas.
Was the impact of reducing lane widths and reducing shared vehicular road space on motorcycle safety considered as part of these proposals?