Calcutta, Aug. 4: Mamata Banerjee today held the Damodar Valley Corporation (DVC) responsible for the deluge in Bengal, but senior government officials said targeting the central agency was an oversimplification of the situation that had affected more than 61 lakh people across the state.

"I spoke to Piyush Goyal (the Union power minister) this morning. I told him the DVC is releasing additional water from its dams, causing floods in Bengal. The DVC does business in the state but it is causing floods by not holding water to capacity in the dams on a regular basis," the chief minister said.

"I got to know that the DVC released up to 2 lakh cusecs of water, causing floods in several blocks. This is happening because the DVC dams have failed to hold water up to their capacity because of lack of dredging and modernisation," she said. Mamata did not mention when the amount was released.

DVC officials denied the allegation, saying the corporation released much less water than the carrying capacity of the downstream of the Damodar. They said the volume of water released a day for the past few days was less than the carrying capacity of the river's downstream, which was 1,11,000 cusecs.

Cusec means cubic foot per second. As neither Mamata nor the DVC officials mentioned the duration of the discharge, the allegation and its rebuttal remained hazy in detail.

"I am not sure about the duration of the release. But if the number of hours is not mentioned, the standard practice is to assume that water was released for 24 hours," a river expert said.

Samir Maji, the manager, reservoir operations, of the DVC, said water had been released in keeping with a decision of the Damodar Valley Reservoir Regulation Committee, headed by a member of the Central Water Commission. The committee has the chief engineers (irrigation) of Bengal and Jharkhand among its members.

Maji said the DVC had to release water to prevent damage if the levels were close to 495 feet and 425 feet, respectively, at Maithon and Panchet.

Senior state government officials said the chief minister had tried to point out that the storage capacity of the Maithon and Panchet dams had decreased because of siltation.

"I had written to the Centre during the tenure of Manmohan Singh in 2013 mentioning the problem, but nothing was done.... You (the DVC) are not modernising the dams and we are suffering. I have been saying this for long and I will again take up the issue with the Prime Minister during my visit to Delhi between August 11 and 12," Mamata said.

While Mamata quoted a figure of 2 lakh cusecs, state government officials said the DVC released less than 1 lakh cusecs of water on average in the past few days.

"Yesterday, the combined release of water from the Maithon and Panchet dams were 95,000 cusecs. Today, the figure was around 94,000 cusecs. This has more or less been the average release from the DVC dams in the past few days," a senior state government official said.

The official's comment suggests that areas located in the Damodar's downstream were flooded despite lesser volumes of water being released from the dams than the holding capacity of the downstream, which is looked after by the Bengal government.

According to DVC officials, the basic problem plaguing the Damodar downstream was siltation on the riverbed and at the Durgapur barrage. They said there was siltation in the channels that carry water from the Durgapur barrage.

"According to the Central Water Commission, it is more difficult and expensive to dredge dams than barrages and their channels. As the Durgapur barrage and its channels are controlled by the state government, it should have taken the initiative to dredge the paths to avoid overflowing of water," a DVC official said.

An official said the water-holding capacity of the Durgapur barrage from upstream had decreased over the years from around 2.5 lakh cusecs to a little over 1 lakh cusecs because of siltation.

According to some senior government officials, the chief minister is bypassing two major issues.

First, the state government has to undertake a desiltation programme at the Durgapur barrage and its channels.

"The second one is more important. The chief minister should demand that the DVC complete constructing the dam on the Barakar river at Belpahari in Jharkhand. This would control the flow to the Maithon dam. The dam at Belpahari is yet to be commissioned," a senior Bengal government official said.