In a bid to clean the waters of the famous Naini Lake and to restore its eco-system, lake development authorities in Nainital have begun an aeration project.
"The lake conservation project is a 4.75 crore initiative. This is to clean up the lake. The oxygen level is nil beyond eight metres from the surface. Through this project, we are recharging the lake with oxygen right from the bed of the lake to the surface. Oxygen deficiency has led to an unbalance in the eco-system," said Dheeraj Garbival, Secretary, Lake Development Authority.
This is the first time ever that this modern technique is being used in the country, Garbival added.
The system consists of two compressors, which are connected to aeration discs placed in the basin.
The compressors, housed in two separate buildings, will be operated as per requirements based on the concentration of the dissolved oxygen, thermal stratification and season.
The project is expected to increase the transparency of the lake, decrease the concentration of toxic gases and the production of algae, replace undesirable flora and fauna and create conditions suitable for the growth and breeding of fish.
However, residents are apprehensive of the system as they have witnessed an increase in dead fish following the installation of the system.
"After they installed the plant the very next day itself dead fish rose to the surface. So, we were frightened," said Yashpal Rawat, a resident.
Ashutosh Mishra, a scientist, said the surfacing of dead fish is only an initial phenomenon caused by the working of the system.
"Because of the aerators that have been installed there (lake), a break in the thermocline and mixing is taking place in the lake. Oxygen from the top is coming down and nutrients from the bottom are going up. When this happens oxygen near the surface gets reduced. The fish will die initially but later on there will be no problem," he said.
The fish in the lake have been a great help in bringing down the level of pollution and maintaining the biotic balance.
Experts are also of the view that to keep the pollution in the lake water in check, it is important to maintain the fish population at an optimum level.
Naini Lake, situated at an altitude of 2000 feet above sea level and surrounded by green hilltops, is a major tourist attraction. It is also the main source of drinking water for the resort.
However, over the years, a growth in population, development in the area, increase in human activity and raw sewage are threatening the survival of the lake.
Nainital is known as the "Switzerland of India"" because of its picturesque lakes.
It has been privileged with as many as 60 lakes. With the passage of time some 40 lakes disappeared because of deforestation, pollution and a general lack of awareness.
If Nainital has still remained a tourist's paradise, the credit largely goes to its Naini Lake. But now even the survival of Naini lake is threatened.