Lord Street has been identified as a primary regional road in a draft of the State Government's latest overarching planning guide, Perth and Peel@3.5million.
Main Roads and the City of Swan are collaborating on the design of the road while the Public Transport Authority is examining how to improve the efficiency of bus services currently delayed by heavy traffic.
The City has confirmed its vision for Lord Street's upgrade includes a dual carriageway from Gnangara Road in Ellenbrook to Suffolk Street in Caversham with a dual use path and bus rapid transit system.
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READ NOWThe timing of the project depends on State Government funding, of which there is currently none.
The daily traffic volume on the single-carriageway street is currently around 18,000 vehicles per day and quickly increasing as suburbs feeding off Lord Street continue to grow.
A Department of Transport spokeswoman said construction of NorthLink WA would relieve some of the traffic pressure from the Ellenbrook area shifting on to the new highway.
But the population in areas along Lord Street south of Ellenbrook presents more complications.
Forecasts suggest the population of Lord Street's surrounding suburbs " Brabham, Dayton, Caversham and St Leonards " is expected to boom from about 6000 to nearly 20,000 by 2021.
Swan chief executive Mike Foley said the City was working with the Department of Transport to determine the funding for the upgrade. He said once detailed designs were ready, land for the project would need to be acquired.
"The land acquisition process requires that the required land is very detailed so that negotiation can take place with landowners," he said.
Many homes bordering Lord Street have remained in the Metropolitan Region Scheme transport reserve since the Perth-Darwin Highway was first planned to go along Lord Street.
West Swan MLA Rita Saffioti recently released a petition calling on the Government to reduce congestion by upgrading Lord Street and building Henley Brook Avenue between Gnangara Road and Reid Highway.
"The Government has not properly planned for the massive growth in the West Swan area, leaving residents to deal with sub-standard roads and the resulting congestion," she said.