The Victoria in Future 2019 report forecasts significant population increases per annum across metropolitan areas and major regional centres in the next 20 years but not the south-west.

Warrnambool's population is tipped to increase by 0.8 per cent, the equivalent of 5070 people, by 2036. Moyne Shire is the only other area in the south-west expected to increase with predictions at 0.7 per cent or 2140 people.

Corangamite, Glenelg and Southern Grampians shires are all expected to lose residents with a combined loss of 3270.

The report predicts that by 2056, Warrnambool and the south-west's population would increase by 8900 or 0.2 per cent.

In comparison, Victoria's overall growth is set to rise by an average of 125,000 people per year and reach 11.2 million by 2056.

Previously it was expected Warrnambool would reach an approximate 45,000 residents by 2040 but the latest data suggests it will only reach 39,930 by 2036.

Corangamite Shire mayor Neil Trotter is well-aware of the declining statistics for his shire but is hopeful strategies in place will prevent a large decline.

"It is something we are concerned about and it's not something we can turnaround easily. But we are working at it," Cr Trotter said.

"We have a changing age demographic, there is an aggregation of farms to become more viable, families are smaller than they once were, children are leaving for boarding in high school or for tertiary education and our houses are being converted for BnB use rather than being occupied.

"But there are still great opportunities here and we have many strategies in place to attract people. health care, accountancy and agriculture are just some of the sectors with great opportunities.

"We have the rural living strategy created for more housing. Our waste water treatment plans are designed to attract more people to the smaller towns and we have the population and migrant plan in place and we'd love to see more migrants taking on the opportunities we have here.

"But there is a great need for transport access, network upgrades and late services. These significantly impact the livability of our area."

Southern Grampians chief executive Michael Tudball said the government figures used throughout the report did not reflect the area's current population increase.

"In the past 12 months until May, the Southern Grampians has grown by 0.3 per cent," he said.

"We have strategies in place for this and they're working. Our economic migration program has seen 10 families move to the area from Melbourne or Adelaide and these residents are in our houses, jobs and schools.

"The south-west shires are creating an environment for young people to move here for jobs opportunities. Jobs aren't the issue, it's finding the workforce to fill them and we've put in significant investments to advertise this through metropolitan and other regional areas.

"We have housing, jobs and this is a livable area, the problem is we're a minimum of three hours from Melbourne. Public transport is not well-sourced out here and we're pushing for the western railway service for trains to the Southern Grampians.

"Locally, we're confident in our figures."

Also facing a decline, Glenelg Shire mayor Anita Rank hoped government support could improve the decreasing population figures.

"Council is working on a number of initiatives to reverse the net population loss predicted for our shire over the next two decades and to shore up our skills shortages," she said.

"The data is currently indicating our population is growing in the baby boomers and civics sectors with a corresponding decline in the iGen and Gen X. This decline is in generation x and millennials which is essentially the young families' segment driving workforce growth.

"We need continued government support with decentralisation focused programs and strategic job creating investment to reverse this trend. With almost zero unemployment, we offer a convincing package of vast job opportunities and affordable living.

"The creation of the thisisportland (campaign) is just one step our council is making to make the sea or tree change transition a reality for a city-based family.

"Furthermore, our efforts to diversify the economy with new investment in renewables, tourism and agriculture are creating more jobs and growth opportunities."

Even with a predicted increase, chief executive Bill Millard said Moyne Shire was working on attracting more people to the area.

"Council experiences moderate population growth, with most growth occurring in the coastal areas and challenges in the northern parts of the shire," he said.

"Key priorities for council are to encourage people to move to Moyne through showcasing our towns and lifestyle opportunities and by focusing on economic development opportunities.

"These opportunities include diversifying agriculture outputs, boosting our tourism sector, enabling business development and attracting investment."

Victoria, the second largest state in Australia, has been growing by 150,000 per annum which is the highest rate of 2.5 per cent on average.

The Department of Environment, Land, Water and Planning's Land Use and Population research team, which produced the report, suggested growth was being driven by increasing numbers of births, longer life expectancy and strong migration from overseas and interstate.

The report also expects migration will continue to settle in Victoria while the number of births will increase from almost 80,000 per annum to 120,000 by 2050. Life expectancy for those born in the mid-century will rise to 87 for males and 88 for females.

Warrnambool City Council were approach for comment.

Have you signed up to The Standard's daily newsletter and breaking news emails? You can register below and make sure you are up to date with everything that's happening in the south-west.