Warbling magpies and purple swamp hens greet Peter Hancock as he wades into Dumaresq Dam for his morning ritual.

He’s been going there for more than 20 years and though he also swims in pools and oceans, the dam offers something special.

“A lot of the larger dams don’t have the developed ecology of Dumaresq Dam,” the freshwater ecologist said.

“It’s a nice spot and there is always interesting wildlife.

“Sometimes it feels like your own private lake.”

Peter hasn’t missed his morning swim for more than two years.

After his 600th consecutive day, he learned of a man in New York who had achieved 1000 days in a row.

Today is day 943.

Each swim, Peter sets a buoy to measure the dam’s temperature and he wears a GPS to track his swim.

At its coldest, in mid-winter, the dam reached a little over 4 degrees, though each year since he began recording the temperature has increased.

In 2016 he recorded 7.4 degrees. You might think this means wearing a heavy wetsuit but Peter says it's more practical to just wear Speedos.

“You lose your fine motor skills when it’s that cold and it’s just too hard to get a wetsuit on and off,” he said.

This is not the first challenge Peter has set himself either.

In 2014 he swam in 333 different locations in the one year, including in the 1.6 degree Fox Glacier River in New Zealand.

In all, Peter has clocked thousands of kilometers in lakes and rivers throughout the region and when you ask him why he does it, he’ll tell you it’s just a great way to clear your head.

November 26 is Peter’s thousandth day and to celebrate, family and friends will hold a barbeque at the dam.