RedSquare Traffic's team performing a turning movement survey at the above intersection saw a near miss crash that could have resulted in a fatality or a serious injury. A car approaching from northwest having successfully avoided a potential rear-end crash at Outlet Road, had to avoid another conflict at the gravel road further southeast (Coghlans Road). We couldn't help but notice the below par spacing of the two intersections (Outlet Road and Coghlans Road), which is currently at 109.7m, where it should ideally be 275m in a rural 100km/h zone. The 275m space is known as the functional area of an intersection. It goes without saying, the geometry of the other legs of this intersection only makes this intersection a complex one, in a rural context.
Austroads Guide to Road Design Part 4 defines this situation as "Stopping distance is a method of assessing the required downstream distance. This allows a driver to pass through the intersection before having to decide that it is necessary to stop because of a conflict at a downstream access connection".
It is true, in a rural context it may not always be necessary to provide the distances specified on the standards and regulations especially due to low turning traffic volumes. However, it is always in a scenario like this that crashes are likely to happen as drivers have low expectations of turning vehicles. Lack of street lighting only make it worse.
A common traffic engineering solution is to provide a basic auxiliary right turn (BAR) treatment or to provide a widened shoulder to allow for a vehicle to get around a stopped/stopping vehicle without causing a rear-end crash. This also increases space available for an emergency manoeuvre to avoid unexpected conflicts at an intersection.
Keep your eyes on the road. It only takes a millisecond for something terrible to happen.
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