THE Wanneroo Road-Joondalup Drive intersection would reach a state of gridlock within a decade if upgrades are not done, Mains Roads WA says.
Spokesman Dean Roberts said although congestion had decreased since the Mitchell Freeway extension to Hester Avenue opened, traffic modelling showed it would get worse.
“Overall performance at the intersection will deteriorate to an unacceptable level within five years before reaching a state of gridlock in the late 2020s,” he said.
“The modelling confirms that a grade-separated interchange is required to alleviate projected levels of congestion arising from ongoing commercial and residential development east of Wanneroo Road.
“It also confirms that by undertaking construction now, while the intersection still has some capacity, disruption to road users can be minimised.
“Delaying the project until congestion materialises would result in major construction impacts and disruption to the surrounding road network.
“The project is in Main Roads’ approved program of works to proceed during 2018-2019 and 2019-20 in line with the State Government’s commitment.”
Mr Roberts said Mains Roads would keep the community informed as the project progressed and acknowledged calls for more information.
“A series of community information sessions are proposed for the next month which will enable interested residents to view the plans and speak with key members of our project team in an informal and personal setting,” Mr Roberts said.
“We are currently finalising the logistics and will publicise dates and times widely in the coming weeks.
“Main Roads continues to liaise with the project’s community liaison group during the development of design and other matters such as traffic management, noise and vibration to minimise impact to adjacent residents.”
Mr Roberts said upgrades to the Joondalup Drive-Cheriton Drive and Wanneroo Road-Clarkson Avenue junctions had been included in requests for proposals, but he could not provide more information as a live procurement process was underway.
He said the decision to build the bridge over Wanneroo Road was based on which road had the most traffic movement.
“Traffic surveys demonstrate that volumes on Joondalup Drive are two and a half times greater than on Wanneroo Road,” he said.
“Joondalup Drive is the major east-west route used to access Joondalup city centre, the Mitchell Freeway, the train line and coastal area.”
Upgrades to Flynn Drive and the future Whiteman to Yanchep Highway feature in transport modelling for the greater Perth road network.
“This model framework was used to assess the Wanneroo Road-Joondalup Drive interchange and has informed the development of the proposed design,” Mr Roberts said.