While floods in Assam dominate headlines during the rains, erosion is a bigger menace whose effect is felt longer. It requires round-the-year scientific management of the river channel to keep erosion under control. But sand mafias and unscrupulous brick kiln owners work in cahoots with corrupt foresters and other government officials to dig up river beds and banks. These rackets flourish during the dry season all over the State, playing havoc with river channels. The authorities concerned look the other way so long as they get their ‘commissions’, but the damage is there for others to see, including picnickers who throng scenic, secluded riversides during this season. On the outskirts of capital city Guwahati, a few such spots are located in the section between Narengi and Chandrapur alongside the Brahmaputra. Those who are observant can see plenty of tell-tale signs of the riverbed haphazardly dug up or earth cutting on steep banks. Such activities are carried out clandestinely at night, though it is not uncommon to see operators doing such things brazenly during the day. People usually mind their business, thinking these operators may have wangled a permit from somewhere, but many are doing this illegally after lining the pockets of officials. Under the cover of darkness, hundreds of trucks and dumpers carry sand and soil to construction sites in the city. There is a need for public awareness about the relationship between the bed of a river and its banks — which is dynamic, complex and sensitive to small changes. Rampant sand mining makes the channel deeper, which can induce bank collapse; as channels become deeper, the water level drops steeply, which in turn causes lower water table in the surrounding area and hurts farm output; the fragile riverine ecosystem can be badly hit, sometimes irreversibly. Once the monsoons arrive, the absence of sand bed makes the river flow turbulent, thereby subjecting the banks to heavy erosion. In the longer dry season, the State is getting burdened with more and more degraded rivers. While corrupt forest and environment officials make merry with the mafias, the agriculture and irrigation departments remain uncaring and somnolent. Among vital issues people need to be activists about, the health of rivers should figure in the top bracket.