GUWAHATI, April 3 - �Dredging is both difficult and expensive and is not at all suitable for the Brahmaputra river,� said noted river engineer and former Secretary of the State�s Water Resources Department Nomal Chandra Das. He was talking to this newspaper on the latest government proposal to dredge out the silt from the Brahmaputra and to build two express highways along its banks by using the excavated silt.
To substantiate his assertion, the river engineer referred to the �Master Plan of Brahmaputra Basin, Part-I� prepared by the Brahmaputra Board for the main stem of the mighty river in 1986.
He quoted the master plan as stating, �Dredging is often advocated for channel improvement. While it is useful in a small way in connection with the channel clearance for navigation, it provides no permanent remedy for the river problems as it does not touch the root cause of these problems.�
He said in the 1960s, an attempt was made to channelise the Brahmaputra at selected reaches on an experimental basis. A big dredger was brought for the purpose. This dredger had a double-action capacity � dredging and dumping the muck.
It was used to excavate silt at some select reaches during the lean season. But after the flood season, it was found that the excavated reaches of the channel were filled up by new loads of silt. Thus, the dredging attempt failed and the idea was abandoned. The dredger was then sold out.
Therefore, the latest proposal to excavate the Brahmaputra bed to deepen its course to maintain a regular uniform flow of the river for navigation and checking its inundation of the human habitats and farmland on the country side, is seemed to be a non-viable one, he said.
Referring to the assertion made by certain quarters that the British rulers used to dredge the bed of the Brahmaputra regularly, he said that during the lean period, the British administration used to excavate the bed of this river, wherever necessary, by using dredgers to maintain a regular flow. This was done with a view to maintaining a navigation channel from Sadiya to Dhubri.
After the devastating earthquake of 1950, the entire bed of the Brahmaputra, particularly in upper Assam, was disturbed. The bed of the river was raised by about one metre in Dibrugarh and its adjacent areas by the debris brought from the Himalayas by its main channel the Dihang (which is known as the Yarlung Tsangpo in Tibet) and its (Brahmaputra�s) other tributaries.
This disturbed the regular flow channel maintained by the British rulers. Considering the high cost, the idea of reviving the regular flow channel of the river was abandoned since the 1950 earthquake. The effort made to revive the regular flow channel of the river made in the 1960s also became unsuccessful, said the noted river engineer.