Located in the Blue Mountains, the intersection provides direct access into Blackheath Village. Blackheath is a busy tourist destination with many visitors travelling from Sydney.
Visitors arriving from Sydney by car, turn right from the Great Western Highway into Blackheath. This manoeuvre requires drivers to wait for a gap in oncoming traffic to turn across two-lanes on the Great Western Highway. Sometimes, the wait can result in driver frustration and risk-taking behaviour.
To improve the level of safety for people turning right into Blackheath, our team was requested to investigate opportunities to install a right-turn green phase into the traffic signal operations. The implementation of an additional phase was complicated by the presence of a Railway Crossing.
A railway line runs parallel to the Great Western Highway and cuts across Bundarra Street at its intersection with the Highway and Govetts Leap Road. The rail line carries both passenger and freight rail services and creates significant variation to the signal operations. When a train approaches Blackheath, all movements into and from Bundarra Street are halted. The timing of the closure depends on the length of the train, which varied from three passenger coaches to kilometre-long freight trains.
Our team created three potential options and tested each using SIDRA modelling software. The options included manually adjusting phase timings to optimise the signal operations.
We successfully generated a signal design which improved safety for right-turning vehicles and caused minimal additional delay or queueing at the signals.
