Posing a severe threat to the ecology in the Bangalmkadavu - Idathikavu region, the sand bed of Pamba River is found to be disappearing fast. The hard rocks are clearly visible under the surface of the river at Bangalmkadavu - Idathikavu areas.

There were huge deposits of sand at Banglamkadavu where Kallar River and Pamba River merge. However, now, the river is left with nothing but hard rocks. Mud and sand had been eroded from the foundation of the pillars of the Bangalmkadavu bridge. The piling of the pillars, in the shape of a well, that was buried under the sand is also clearly visible under the water.

Vast swathes of rocks could be seen under water at Chambon, Mundaplackal, Madaman Vallakadavu, Poovathumoodu, Mukkam, Athikayam, Kadumeenchira, Kattikkal, Paruva, Kudamurutti, Thonikadavu and Perumthenaruvi. There is no water here other than the water that is collected between the rocks.

Earlier, there were huge deposits of sand in these areas. Sand deposits were seen in many areas starting from the check dam at Edathikavu, that was built for the Perumthenaruvi hydroelectric project. Besides, sand was filled in the depths of the water in many areas. Meanwhile, in some places, sand could be seen at the level of the banks, causing minor flooding during the monsoon.