KEY POINTS:
The most extraordinary thing about Australia's largest lake is that most of the time you can't see it. That's because most of the time the vast Lake Eyre Basin - all 120 million hectares of it - is bone dry.
But at present you can see the lake because heavy rains to the north are sending vast torrents of water flowing into the giant salt sink, which usually lies at the bottom of the basin.
Huge flocks of birds - including thousands of pelicans, branded stilts, rednecked avocets, gullbilled terns, ducks, ibis and silver gulls - have already arrived in pursuit of the explosion of algae, salt shrimp and yellowbelly fish which comes when the lake starts to fill.
As usual, the pelicans were at the head of the queue, thanks to an ability to detect the lightning which always accompanies the rain, starting to arrive less than 24 hours after the arrival of the first water.
Not far behind were the eccentrics of the Lake Eyre Yacht Club - motto: "Ya gotta be jokin'. No we're not" - keen to take a rare opportunity to actually sail.
Amazingly, considering Australia is locked in an appalling drought, the water inflow is so strong that locals are speculating this might be the year that the lake fills, something that has only happened six times since it was discovered by Edward John Eyre in 1839.
To see this emerging phenomenon you must make your way to the tiny town of William Creek, usually famous for being the smallest town in South Australia (population either nine or 16 depending on who you ask), sitting in the middle of Australia's largest cattle station, Anna Creek Station (just over 3 million hectares), and just down the road from its longest place name, Lake Cadibarrawirracanna.
But these days, it also offers a route to the best view of the country's largest lake, courtesy of Outback pilot Trevor Wright, who takes off from the William Creek dirt air strip, flies over the racecourse, points his workhorse Cessna 172 east ... and there it is.
For a lake that until recently wasn't there, it is incredibly big, the northern shore almost disappearing in the distance, even at this height.
The huge 1m thick salt pan, solid enough for Sir Donald Campbell to set a world land-speed record in his piston-engined Bluebird in 1962, is now liquid.
But this is not a lake like any other. The surface has an extraordinary range of pastel colours - blues, browns, purples and greens - caused by the different minerals soaked up by the floodwaters. Some of the surface patterns caused by the mixing of different-coloured currents look like something out of science fiction.
Around the edges of the lake are ancient creeks, many of them dry for years or even decades, suddenly flowing again.
And on all sides, plants bloom, sucking up the water, covering the desert in a carpet of green and yellow.
Wright takes the plane down to 100m and a distinct fishy, salty smell, reminiscent of the sea, fills the cockpit.
Then we take off after a flight of pelicans whose image, amazingly, appears in triplicate: the birds, their reflections in the lake, and their shadows.
There are said to be 85 species of birds taking advantage of the lake's presence, and flocks are everywhere.
It's an extraordinary sight and Wright, who must have flown over Lake Eyre a thousand times, says every time is different. "I never tire of looking at it. I think it's incredible to see this water in the middle of the desert."
What makes it all the more remarkable is that "it takes the water perhaps 30 days to get here, flowing down to the lowest point in Australia, 16m below sea level.
"When it arrives it brings with it all the birds and creates all sorts of spectacular colours and patterns.
"It brings the desert to life as well as bringing the tourists to the Outback."
* Paul Estcourt flew over Lake Eyre as guest of the South Australian Tourism Commission.
Checklist
Lake Eyre
Getting There
Air New Zealand flies from Auckland to Adelaide non-stop three times a week and will increase this to five flights weekly from October 29. See www.airnz.co.nz.
Regional Express Airlines operates a service from Adelaide to Coober Pedy. See www.regionalexpress.com.au
Accommodation
The Desert Cave Hotel boasts that it is the only underground international hotel in the world.
What to do
Wrightsair offers flights over the Outback, including Lake Eyre. See www.wrightsair.com.au
Further information
General information about South Australia is at www.southaustralia.co.nz
