Mr Kumar also protested against the proposed reservoir at Buxar and in Uttar Pradesh enroute Allahabad-Haldia waterway.
"We had made the demand to decommission Farakka barrage in West Bengal to the previous UPA government. I told this to Prime Minister Narendra Modi also that the Farakka dam is causing heavy siltation in river Ganga which is a major reason for heavy floods every year in Bihar," Mr Kumar told reporters.
"Many experts have also pointed out the disadvantages from Farakka dam and its original engineer from West Bengal involved in construction of the barrage had opposed it and was forced to leave the job," the chief minister said in order to buttress his argument.
"I have made the demand against Farraka barrage at every platform as its a leading cause for deposit of silt in Ganga river and also hampering flow of the mighty river," he said after a "Lok Samvad" (public dialogue) programme.
He said that during the previous UPA government of Manmohan Singh, the state had taken the then Water Resources Minister Pawan Bansal to the barrage to show him how it was causing problem to Bihar and other riparian states.
"During flood last year when PM Narendra Modi had talked to me I had told him about disadvantages accruing from Farraka dam and during a meeting with him explained this in detail also," Mr Kumar said.
"There is no benefit from Farakka dam...get a study done on it," he said.
Asked about West Bengal's stand on the dam, he said that state is also adversely affected by it but "I do not focus on what others say or is doing on this, since Bihar is affected by it grossly we are protesting against the barrage".
Mr Kumar also protested the proposed construction of reservoir at Buxar enroute Allahabad-Haldia national waterways number I.
"Cleanness of Ganga is possible only when there is unhampered flow of its water," he said. Kumar, who visited Punjab's Seechwal village yesterday to see the low cost water treatment developed by environmentalist Sant Balbir Singh Seechewal, said Bihar would take help of the Seechwal model.
Seechewal, and Magsaysay award winner waterman Rajendra Singh have been invited for the two-day national seminar in Patna from February 25 on better water conservation and environment protection, he said.
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