Western Power crews have been given access to parts of the area affected by fire in Banjup, in the City of Cockburn, to assess the level of damage to the electricity network.
Early assessment has found 39 power poles have been damaged by fire and will need to be replaced.
Western Power crews are ready to start rebuilding the damaged network and will continue to work with DFES to get safe access.
Approximately 500 properties in the area lost power when the fire commenced yesterday.
Western Power has managed to restore electricity to many homes but 120 are still without power and are likely to remain so during the day while the network is rebuilt.
Some homes may need an electrician to check their wiring is safe before it is reconnected to the network.