Floods bring focus back on desilting

Vibha Sharma

Tribune News Service

New Delhi, August 25

While levels of the Ganga continue to pose threat, Chief Minister Nitish Kumar’s assertion to Prime Minister Narendra Modi on the need of a “national silt management policy” is expected to initiate movement in the direction which has so far been dealt with in an “ad hoc manner”.

Government functionaries indicate the suggestion has “re-started” the thought process for a proper management of this very real and recurring environmental problem — rising level of silt in rivers due to various factors, including infrastructure projects like dams, and posing recurring threat to man and property, year after year.

The water retention capacity of the Ganga and other rivers has reduced due to siltation, becoming one of the major causes for flooding, says environmental expert Himanshu Thakkar. Lamenting the “ad hoc manner” in which this very crucial issue of siltation is being dealt currently, whether it is while building infrastructure projects on rivers or for navigation purpose, he calls for a concrete effort.

“It is strange how silting does not find a mention either in the National Water Policy or any other document built for management of water resources in the country,” he says. “There has been no concrete effort in this direction so far even while we are talking of building inland waterways and other infrastructure on rivers,” he adds

Now the reason why there has to be a national policy for “silt management” or “de-silting” is for the following reason. As per experts, run of a river till the delta an extremely dynamic process involving several factors—water, silt and biodiversity — a reason enough for tackling the issue comprehensively, keeping all of them in mind.

“Along with water, a river transfers silt from mountains to the delta. Fertile plains formed all along are a result of this process. Any imbalance in this process is bound to create environmental issues. Deforestation results in increase in silt load and construction of dams, as happened in this case, stops the transfer. Less silt at delta will cause a major imbalance vis-a-vis sand in sea,” explains Thakkar.

Which is one reason why “avoidable flood disaster” in Bihar and UP” are being attributed to mismanagement of two dams — Bansagar at Sone in Madhya Pradesh and Farakka on the Ganga in West Bengal — and decreased capacity of rivers to carry the water.