NSW trials smart speed limits at Upper Hunter rural intersection
New smart intersection technology that automatically lowers the speed limit when vehicles approach a busy highway will be trialled for the first time in NSW.
The Rural Intersection Speed Zone (RISZ) system will be switched on at the intersection of Ulan Road and the Golden Highway near Cassilis, between Merriwa and Dunedoo, in early August.
Radar will detect vehicles approaching the highway from Ulan Road and trigger variable speed limit signs on the Golden Highway.
Temporarily slowing highway traffic is intended to improve rural road safety by creating safer gaps and give motorists more time to react. It should particularly help drivers of trucks and other large, slow-moving vehicles turn onto the highway before its usual speed limit is restored.
By using smarts to change the speed limit dynamically, the trial will aim to reduce both the likelihood and severity of crashes at rural intersections, without permanently lowering speed limits along high-speed roads.
The self-contained system is solar powered and incorporates radar vehicle detection, variable speed limit signs, communications equipment and remote monitoring. Transport for NSW will oversee it through a central control system.
Transport for NSW’s Operational Technology Infrastructure team designed and built the system at Yennora in Western Sydney.
Similar systems called Side Road Activated Speeds (SRAS) are in operation in 20 sites across eastern Victoria, including on the South Gippsland Highway at Fish Creek-Foster Road and on the Hume Freeway at Tallarook.
NSW Roads Minister Jenny Aitchison said the trial would explore how technology could address emerging road safety challenges.
“The technology uses radar to detect vehicles approaching the intersection and temporarily lowers the speed limit on the highway,” she said.
“This creates safer gaps in traffic, helping larger and slower vehicles enter the highway more safely.”
The Cassilis installation will be the first such system tested in NSW. The 12-month trial forms part of the NSW Government’s broader Smarter Highways program.
