The Fremantle rail bridge will remain closed until at least Monday, September 1.
The bridge was hit by a cargo ship which broke its moorings during a storm on Sunday, August 17.
Transperth spokesman David Hynes said engineers had spent the week assessing the damage to the track and structure and there was no major structural damage.
"However one of the piers sustained some damage and must be repaired," he said.
"In addition an overhead power structure has been damaged and will need to be fixed."
Transperth is hoping that the bridge will reopened by Monday, September 1. In the meantime replace buses will continue to operate between North Fremantle and Fremantle stations with trains still running betwen Perth and North Fremantle.
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