The cost of the multi-million footbridge across the Swan River from East Perth to the new stadium at Burswood could blow out to a whopping $70 million.

The steel cable-stay bridge, which will give sport punters a seamless walk to the Perth Stadium from the city, was originally budgeted at $54 million by the Barnett government.

WA engineers previously expressed concerns the Perth Stadium footbridge could collapse due to poor welds.

But according to the Sunday Times an extra $16 million could be added to the bill to finish the construction on the distinctive "ribbon" bridge, which is expected to carry 14,000 footy fans on game days once the new stadium opens for the 2018 AFL season.

Bridge's builder York Rizzani has asked the WA government for an extra $9 million due to the change in the alignment of the bridge last year.