50,000-yr-old Lonar Lake in Maharashtra turns pink mysteriously, experts surprised

Nagpur: In an interesting phenomenon, the water of Maharashtra's famous Lonar crater lake in Buldhana has mysteriously changed its colour to pink, thus sparking theories and concerns alike. The change in colour of water of the lake, having a mean diameter of 1.2 km has also left forest officials and scientist puzzled as on normal days, the lake appears stays greenish in colour.

Experts say this is not the first time that the colour change has happened, but this time it is more glaring.

The 113-hectare Lonar lake, also known as Lonar Crater, in Buldhana district of Maharashtra, was created by an asteroid collision with earth impact during the Pleistocene Epoch some 50,000 years ago.

The lake, which is a notified national geo-heritage monument, has saline water with pH of 10.5, Gajanan Kharat, member of the Lonar lake conservation and development committee, told PTI. "There are algae in the water body. The salinity and algae can be responsible for this change," he said.

"There is no oxygen below one meter of the lake's water surface. There is an example of a lake in Iran, where water becomes reddish due to increase in salinity," he noted.

Meanwhile, the forest department has been asked to collect sample of water and dig out the reason behind the changing colour of the lake. 

Kharat said the level of water in the Lonar lake is currently low as compared to the few past years and there is no rain to pour fresh water in it. "The low level of water may lead to increased salinity and change in the behaviour of algae because of atmospheric changes...This may be the reason for colour change. This is not the first time that the colour of water has changed," he said.

Dr Madan Suryavanshi, head of the geography department of Aurangabad's Dr Babasaheb Ambedkar Marathwada University, said that during the lockdown phase, there may not have been any disturbance to water which led to this change.

The oval-shaped Lonar Lake is a part of the 383-hectare Lonar Wildlife Sanctuary declared on June 8, 2000 as part of the Deccan plateau. It was identified as a unique geographical site by a British officer C J E Alexander in 1823, and also declared a notified National Geo-heritage Monument in 1979.