Ms Wran said her husband, who died in 2014, regarded the museum as one of his greatest legacies.
''The logic of removing one world-class institution on the perfect site for what is a unique collection to build another on flood-prone land for a purpose still very ill-defined defeats most thinking people, or people I know,'' she said.
But the director of the Campbelltown Arts Centre, Michael Dagostino, said western Sydney deserved its own state cultural institution with its own identity, vision and daring ambitions.
With Sydney's second airport to be built in the region, a science and technology museum would be a ''fantastic fit'' with community aspirations ''because that's where the innovation is happening''.
''It's important to locate a museum where people live, adding to the cultural vibrancy that already exists in western Sydney," he said
''Living on the doorstep of the new proposed Parramatta museum will mean families like mine and many others will have access to an important cultural institution like never before. Cultural activity should be embedded in the everyday and when a major institution is 30 or 50 kilometres away how can that be possible?''
A 2015 report by Deloitte commissioned by the Sydney Business Chamber found western Sydney had 35 major competitive cultural arts venues including performance venues, galleries, museums and heritage attractions, compared to more than 140 in eastern Sydney.
In terms of performance art venues, this represented two performance arts seats per 1000 residents, compared to 15 in eastern Sydney.
Outside of two state significant historic homes – Government House and Rouse Hill – no major state cultural institution is located in western Sydney, the report said.
Ms Wran said she wholeheartedly agreed western Sydney deserved cultural resources and programming.
''Why can't we leave the Powerhouse intact and have a wonderful new different museum in the west? I would love to see an institution with an enterprising director who invites all the other leading galleries and museums to show their best in innovatively curated exhibitions on a revolving basis.
''Visiting blockbusters could also be scheduled so whether they are coming to Sydney, Melbourne or Darwin they could be scheduled so they include a period in this western Sydney gallery or museum. That way the people of western Sydney get the very best we have got. They don't get a standing display that is permanent and once they've seen it they may not see it too often.''
Mr Dagostino said establishing Parramatta as a satellite centre of the Museum of Applied Arts and Sciences meant it would remain vulnerable to budget cuts and the risk of eventual closure as happened with the National Gallery of Australia in 2016.
''If it's just an annexe of an institution it's something that could easily become the poor cousin, the resources will always remain in the CBD.''
Linda Morris is an arts and books writer for The Sydney Morning Herald.
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