Eastern Maar Traditional Owner John Clarke said an archaeologist determined a bone found by construction workers last Thursday near Colac's Barongarook Bridge was from an animal.

Mr Clarke said workers and police had previously believed the bone to be human and photographs of the bone had been provided to Coroner Court pathologists.

"With our cultural heritage expertise, we were able to determine straight away that it was not human," Mr Clarke said.

"We are quite relieved in fact that it wasn't human remains, it means no further of ancestral remains are occurring in that area. It is a well known burial place and we were concerned about the impacts that could have been brought upon that burial place."

He said a shoe also found was of no significance to Traditional Owners.

Colac police confirmed the discovery was now believed to be animal remains.

EARLIER: HUMAN remains found at the site of an under construction bridge in Colac are thought to be of Aboriginal ancestors.

Major Roads Project Authority workers were excavating near the Barongarook Creek bridge on Colac's Murray Street around 1.30pm on Thursday when they discovered what they believed were human remains.

Project authority program director Tim Price said work was immediately halted in the surrounding area while police were notified.

Detective Sergeant Adam Forehan of Colac police said workers had uncovered a piece of bone and a shoe, which police then assessed as not suspicious and likely ancestral.

"There is no forensic or legal value to these remains and the Traditional Owners will work with people at the scene to progress and finalise the matter," Sergeant Forehan said.

He said the remains were with police and would be repatriated with Eastern Maar Traditional Owners on Friday.

Eastern Maar Traditional Owner John Clarke said an archaeologist planned to excavate the site in coming days to confirm the remains' origin and the presence of any further remains.

"We will be working with Eastern Maar citizens and an archaeologist, and we will be doing that in partnership with MRPV, VicRoads and the contractor building the bridge," Mr Clarke said.

"There is historical records relative to the location being a Gulidjan burial place. In the last 20 years, this will be the fifth ancestral remains found within that immediate vicinity."

The discovery comes after workers found Aboriginal ancestral remains while excavating near the same bridge in March.

The new bridge will replace an 80-year-old bridge on Murray Street as part of Princes Highway upgrades between Winchelsea and Colac.