Responding to a supplementary during Question Hour, Water Resources Minister Uma Bharti said following the construction of Farakka Barrage, the number of hilsa available in the Ganga has gone down dramatically, as the sea water which seeps in, created hurdles in its breeding. The fish breeds in fresh water.
She said plans are afoot to install fish ladders to ensure that hilsa gets fresh water to breed. If it happens, the fish, considered a delicacy in East India, will be available even in the Chambal region of Madhya Pradesh and Uttar Pradesh, as was the case in the past, Bharti said.
Fish ladder is a series of pools built like steps to enable fish to ascend a dam or waterfall and enables them to migrate upstream over or through a barrier.
Bharti said the real benchmark that Ganga is pollution free would be the return of aqua life in the river.
She said the return of river dolphins and gold fish in the Ganga aqua life system would be the biggest benchmark to prove that the river has rejuvenated.
Bharti said dolphins have lost their eyesight due to prolonged exposure to pollution. He said the creature has developed other senses over the years to overcome blindness.
Now, there are plans to release dolphins having eyes, she said, adding if they do not turn blind, then it would prove that the level of pollution in the river has declined.