Regional Victoria's winsome waterfalls may lack the sheer size and grandeur of those of the Congo River, the Zambezi, or the Niagara.

But each of more than 100 charismatic cascades has its own rugged appeal and, thanks to record-breaking August rainfall across the state, they are currently putting on a show.

ABC listeners from across the state flooded the Regional Victoria Saturday Breakfast program with photos and reports demonstrating the power and beauty of falls across the Southern Grampians, the Otway Ranges, South Gippsland and the Victorian high country.

But the prospect of a warm, dry spring means they are best explored now, before the torrent inevitably slows to a trickle.

Waterfall season

Federation University's professor of water resources engineering, Andrew Barton, said this spectacle would not last more than a few months before what is forecast to be a strong El Niño takes effect.

"It's a question a lot of tourism operators, farmers and landowners are all interested in — what's going to happen with our farm dams, our water supplies and our waterfalls?" Professor Barton said.

"We've had quite a good inflow season, with a good rainfall month, lots of inflows through our reservoirs, creeks and rivers, which are flowing nicely.

"But with this Bureau of Meteorology advice of a pending El Niño and perhaps one of the strongest El Niños we've seen, we're all waiting and watching for when those inflows will start drying up, and the rainfall will disappear."

Professor Barton said existing rainfall and inflows should carry these waterfalls until October.

However, November will likely see the countryside start to dry out, which will inevitably reduce flows down rivers and creeks that feed these falls.

"I would expect waterfalls to some greater or lesser extent will be around up until October at least," he said.

"If we get some continued rain, we could maybe push on into November or December, but that's about it.

"Depending how hard the El Niño hits us, a lot of these waterfalls may dry up very quickly."

Victoria's charismatic cascades

Travel guide Undiscovered Victoria has catalogued 50 of Victoria's more than 100 named and documented waterfalls that can be accessed by walking track.

Co-author and publisher Jay Dillon said much of their appeal was in their variety.

"I think we're very blessed in Victoria to have a whole range of different types of waterfalls in different environments to discover and explore," Dillon said.

"They represent a wonderful destination to put on your map and head towards because — especially this time of the year — you will experience a visual delight when you arrive.

"The other thing is there are often those little spaces and nooks along the way that add to the journey."

Millennia in the making

In a geological sense, many smaller waterfalls are fleeting, created and then undone by erosion.

However, many of Victoria's memorable waterfalls formed over periods of time measured in tens of thousands or hundreds of thousands of years.

Some are a million years old and more.

Professor Barton said that when fast-flowing water interacted with a combination of hard and soft material in the earth, such as basalt and sandy loam, it scours away the softer material to create a fall.

"Their origin story starts with the fact that all water, when there's enough of it, and it flows fast enough, is very effective at eroding and scouring out dirt and earth," he said.

"When a river or a creek runs across a landscape where some of the soil will be soft and easy to scour out, and other parts will be quite hard, it's [the harder area] where it forms the top of a waterfall.

"Over time, you get this effect of hard geology upstream, softer geology downstream, and you start getting this elevation difference as that water flows over the top.

"Over years, over centuries, over millennia, that can make quite a dramatic impact on the landscape."

Ten to fall in love with

There are scores of waterfalls to discover around Victoria. These are some of Mr Dillon's favourites:

MacKenzie Falls

The largest of about a dozen named waterfalls in the Grampians/Gariwerd National Park in western Victoria.

It is the largest waterfall in Victoria by water volume, with a drop of about 35 metres.

Nigretta Falls

One of two major waterfalls along the Wannon River (the other is Wannon Falls), which flows from the Southern Grampians region.

Wannon Falls features a large, single plunge, while Nigretta Falls spills into several falls.

Lal Lal Falls

A short drive from Ballarat, Lal Lal has a 30-metre drop over volcanic basalt into a deep gorge. It features a viewing platform for spectacular photographs.

Hopkins Falls

One of Victoria's widest falls with multiple cascades through layers of hexagonal volcanic basalt columns which can be seen from the banks of the Hopkins River.

Situated a short drive from Warrnambool on the Victorian south-west coast.

Stephenson Falls

There are numerous spectacular waterfalls in the Great Otway National Park, including Erskine Falls, Beauchamp Falls and Triplet Falls.

Stephenson Falls drops more than 20 metres into the Gellibrand River.

Narracan Falls

An elegant little fall in the Latrobe Valley that is wider than it is tall, with an eight-metre drop into the Narracan Creek.

Agnes Falls

Cascading nearly 60 metres into a gorge in South Gippsland's Strzelecki Ranges.

Situated a 12-minute drive from Toora on the South Gippsland Highway.

Woolshed Falls

Located in the Chiltern-Mount Pilot National Park, close to Beechworth in north-east Victoria, where Reedy Creek plunges about 15 metres over granite into a pool.

Ladies Bath Falls

Ladies Bath Falls and Eurobin Falls near Bright are a short walk from each other, offering a two-for-one deal for hikers in the Mount Buffalo National Park.

Trentham Falls

A single-drop waterfall within a short distance from Trentham in central Victoria. The Coliban River falls about 32 metres over columns of basalt.

Due to instability caused by erosion, it cannot be accessed directly but can be viewed from a platform.