A Perth family's request to host a fireworks display to spread their loved one's ashes over the Canning River was approved by the City of Canning on Tuesday night.

It is understood the unique memorial ceremony, if given the final green light by the Department of Mines of Petroleum, will be the first of its kind to be legally carried out in Western Australia.

The woman's ashes will likely be shot up into the sky during a fireworks display in March.

The deceased woman's partner told the City of Canning in a letter written in January that it was her wish to have her ashes released with fireworks.

"She wanted to use the Shelly foreshore as this is where we attended Australia Day for many years with the children," he said.