Explained: Why rising water levels threaten Maharashtra’s age-old Lonar lake and nearby structures

Researchers estimating the age of the crater have come up with widely contrasting numbers. A group led by Adam Maloof of Princeton University in 2010 suggested a maximum age of 12,000 years for the impact event. A team led by Fred Jourdan of Curtin University of Technology in 2011 estimated the crater to be as old as 5.7 lakh years.

Various studies say that the pH value of water in the lake is around 10. Any value above 7 is alkaline. This means the lake is uninhabitable for most species. Only specific species that are able to survive in extreme conditions are present in the lake, giving it a unique ecology.

This is where the key issue lies. A rise in water levels could change the pH value and alter the ecology of the region.

Rising water levels 

The lake is fed by multiple streams but has no stream outlet, according to Maloof’s research paper. This means that the only loss of water at the lake happens due to evaporation. However, the current increase in water levels was not sudden.

In total, the water level at the lake has risen by about four metres since 2022, says Chetan Rathod, Assistant Conservator of Forests at Akola. A strong monsoon season in 2025 led to a more dramatic increase in water level in the past few months leading to the Kamalja Devi Temple being partially submerged two meters underwater.

Superintending Archaeologist Arun Malik of the Archaeological Survey of India (ASI) told The Indian Express that there are 15 ASI-protected temples at the lower rim of the lake. Nine of these have been partially or completely submerged, according to the High Court order.

Why has the water level risen? 

Geologist Ashok Tejankar, former Vice-Chancellor of Dr Babasaheb Ambedkar Marathwada University and originally from the Lonar region, was roped in to diagnose the issue. He visited the site in January.

He told The Indian Express: “From the last 10 to 15 years, on the surface people have constructed a number of water management structures like borewells, dugwells, and percolation dams. The borewells are dug 600-700 feet deep and these have led to recharge of lower aquifers along with the dams. The water then flows underground from the lower aquifers to the lake, increasing its water levels ”

The monsoon in 2025, when over 100 millimetres of rainfall took place in three hours, also exposed bedrock of the streams and increased percolation, further contributing to the recharge of the lower aquifers, he said.

Tejankar said that even though the issue of rising water levels was known for the past many years, government authorities ignored it and no preventive action was taken. “Why has the government now taken action or why is there different news? It is there because the temple is now submerged,” he said.

The submerged Kamalja Temple at Lonar lake on January 28. Photo: Arun Malik of ASI

The solution

Malik said that the ASI’s priority is protecting the Kamalja temple and it will start the construction of a “gabion wall” as a temporary precautionary measure to keep the temple safe from rising water. A gabion wall is a retaining structure composed of stacked, wire mesh cages filled with rocks or concrete.

Tejankar recommends that as a temporary solution, water from incoming springs must be diverted or lifted from the surface of the lake. In the long term, a geological and geo-hydrological survey must be carried out. This survey would identify the lower aquifers and the recharge zone, which would enable treatment and cementing of the area.

As the lake is located in Lonar Wildlife Sanctuary, under the Wildlife Protection Act, 1972, water cannot be diverted to or from such a region without appropriate permissions in consent with the state government, said forest conservator Rathod. He said, “We are checking how we can do it in the easiest way and various other agencies are also involved in this effort.”