The Northlink WA Project, which includes the Swan Valley Bypass and Tonkin Highway grade separation, will receive $138 million in funding.
The funding package also includes $12m for upgrades to Great Eastern Highway between Bilgoman Road in Greenmount and Mundaring.
Prime Minister Tony Abbott was in Perth last week to announce the grants, provided as part of a deal to compensate WA for its declining share of the GST.
Under the $499m package, the Northlink WA project will receive an additional $138m, $84m for Tonkin Highway grade separation and $54m for the Swan Valley bypass.
About $67m has also been provided for an upgrade of Reid Highway, or 80 per cent of the overall cost.
Pearce MHR Christian Porter said he had fought to address WA�s declining GST share for the past five years at both State and Federal level.
�Without this grant, WA�s GST share would fall below 30 cents in every dollar we pay, when no other state or territory in the history of the GST has had their share fall below 81 cents,� Mr Porter said.
He described the allocation of GST by the Commonwealth Grants Commission as �unsustainable and broken�.
Mr Porter said the package was designed to compensate WA in a way that reflected a nominal freeze in the decline of WA�s GST at the 2014-15 level of 37 cents in the dollar.
Mr Abbott said the State Government must �pursue further micro-economic reforms� in return for the bail out.
�WA will be able to access significant Federal incentive payments towards further investment in job-creating economic infrastructure when reinvesting the proceeds of any privatisations into such infrastructure projects,� he said.
Swan Hills MLA Frank Alban also welcomed the announcement.
�The government has committed $12m to these essential upgrades,� Mr Alban said.
�I believe many Hills residents, as well as those in the trucking industry, will appreciate the Great Eastern Highway upgrades.�
Mr Alban said the announcements were a direct response to the fact that the State had suffered a GST revenue shortfall for 2015-2016.
Premier Colin Barnett said he appreciated Mr Abbott�s acknowledgment that WA was being treated unfairly.
�This is the first time an Australian prime minister has actually acted to compensate WA for its unfair share of the GST,� Mr Barnett said.
�We still face a tight budget, but this will help.�
Midland businessman Eddie Peters, who has led a vocal campaign on the GST issue, said he believed the announcement was great news.
�But the reality is that (the Federal Government is) still using the GST threshold as a lever to get a bigger slice of the cake,� he said.
�It hasn�t worked and had they agreed with the threshold being dropped altogether, then WA�s share of the pie would be welcomed.�
Mr Peters said there was no confidence in the economy at a state or national level.
�If this changed, it would bring more business, more GST collection and company tax, and that needs to be factored into theGST debate,� he said.
�And people need to buy local.�
He reiterated the buy local campaign was the most important thing residents could do to help the WA economy.
�Think about the freight costs, try to buy local and help a family business that employs West Australians,� he said.