A new trial surface is being laid in two trail sections in Koroit. These sections are between Nine Mile Creek and the Warrnambool-Penshurst, and between Warrnambool-Penshurst Road and Pattison Street.

The materials being used are quarry dust and stone and selected limestone.

The section in each area will cover 300 metres.

Port Fairy to Warrnambool Rail Trail secretary Ian Bodycoat said the trial areas would be assessed in August to see which, if either, was suitable.

"We will have a good indication by August about how they have gone," Mr Bodycoat said.

"This is the first step in finding the best fit and one we will get a lot of years out of. The trail surface now is limestone, but it is 10 years old and showing its age."

In August last year, Moyne Shire Council announced it had won a $600,000 grant to go towards rail trail infrastructure.

Mr Bodycoat said once the type of material to be used was chosen, he was confident the grant would be enough to have the new surface all the way along the trail.

Once that key infrastructure task is complete, Mr Bodycoat said he would be encouraging Moyne Shire to increase its input.

"It would be great if council could find something in its budget each year to spray seal sections of the trial to help protect it," he said.

"The new surface and a regular spray seal would bring us up to the level of other rail trails."