Keri: Rising deforestation, loss of riparian vegetation, unregulated laterite quarrying, and upstream flow alterations are accelerating siltation in the Mhadei river and its tributaries in Sattari, during monsoon. Heavy rains wash loose silty clay and sandy silt into the river, leading to sediment buildup.Geology postgraduate Pankaj Lad said forest clearing in upstream areas has increased siltation, altering natural hydraulic profiles and reducing peak water velocities that flush sediment downstream.Lad also highlighted changes at Kankumbi under the Kalasa nalla project, where Karnataka has completed channels and underground canals to divert Kalasa waters into the Malaprabha basin, altering currents and causing sedimentation in specific zones. Sand extraction has further destabilised riverbeds and increased soil loss.Geography teacher and wildlife enthusiast Subodh Naik said siltation is driven by soil erosion from heavy monsoon runoff, deforestation, hill cutting, road construction, and loss of riverbank vegetation.Naik said silt accumulation reduces river depth and carrying capacity, increasing flood risk during intense rainfall. He said that addressing erosion at the catchment level, protecting forests and riparian buffers, and regulating hill cutting are essential, since desilting alone will not solve the problem.
