There was a training/trialing track on the Dudley Flats, between Dynon Rd and Footscray Rd from around 1914 through to the 1950s.

in 1930, these were the instructions for getting there:
Footscray Speedway is situated close to the swing Bridge over the Saltwater River, on the Melbourne side. It is reached by the main road from North Melbourne railway station to Footscray (Dynon Road), turning off to the left before crossing the river at Footscray and turning away from the river again on reaching the swing bridge.

In 1947...at the time of the opening of night trotting at The Showgrounds, trial results published show:
Trotting Trials At Footscray
Under the auspices of the Melbourne and District Driving Club, public trotting trials were held at
the old Footscray trotting track yesterday afternoon. Most successful driver was J. Bar-
ron, who piloted New Main, and the veteran mare Esme Derby, to vic-
tory.
Among drivers competing were: Tom Allen, George and Albert Gath, Roy Shadbolt, Sif Fahey.

As late as 1950, the track was fenced, and leased by the TCB., with pressure being applied by The Melbourne City Council and Footscray Council to lessees to improve the maintenance of their properties.

Any information about this track would be appreciated.