Melbourne city has its own pink lake. The Salt Lake in Westgate Park in Port Melbourne turns pink when perfect mixture of very high salt levels, high temperature, sunlight and low rainfall is attained. But no one can predict when that will happen.
The lake often turns pink in the warmer months before turning to its usual blue in autumn. The Salt Lake turns pink because of the natural interaction of harmless, single cell green alga – Dunaliella Salina – and also harmless halobacterium – halobacteria cutirubrum – in response to very high salt levels, temperature and light. Dunaliella Salina grows in the salt crest at the bottom and produces a red pigment named “beta carotene”. The colour intensifies as water evaporates in summer heat and salt content increases.
Pink lakes are rare. There are several in Murray – sunset National park in Victoria, some in Western Australia and a few in other countries.
The area originally part of the saltmarsh that extended north from Yarra River up the Maribyrnong River to the present site of Flemington Racecourse, went through a period of extensive sand mining in the 1930s. The excavated land was filled with water to form the Salt Lake.
Apart from the pink lake, Westgate park offers a range of attractions and activities and offers spectacular views to the mouth of Yarra and the city skyline. Westgate park is located at the eastern banks of the Yarra River under the Westgate Bridge.