Sedimentation in river Ganga is the main cause of increasing pollution in the river, says a study carried out by the Geography department of Allahabad University and funded by the Union Grant Commission(UGC). The recently submitted report to the UGC says 4 mm sedimentation per year is reported in Allahabad and Kanpur stretch of the river. The survey was conducted by a team led by Dr S S Ojha, a reader in Geography department, in Phaphamau, Jhunsi and Naini in Allahabad and two places in Fatehpur and Kanpur. He said: “ Till now, it was considered that industrial and human wastes had been polluting Ganga but the study revealed that had the river flown at its natural velocity, the pollutants would have been washed away.” He added: “Silting affected the flow of the water and also caused expansion of Ganga bank that led to frequent changing of its course, causing floods in eastern Uttar Pradesh and Bihar.” In the absence of desilting operations, the river has become shallow over the decades, which hampered the its self purification mechanism, says the report. Besides silting, throwing of polythene, flowers and immersion of idols have blocked the river bed, causing heavy obstruction in groundwater recharging. Ojha said: “While the sand along the banks of Yamuna is used for construction work, sand of the Ganga banks cannot be used due to its clayey nature and hence remains in the river for years.” Taking stock of government schemes, Ojha said: “ Officials of Ganga Action Plan have not undertaken any dredging and the sedimentation has increased several times. Twenty mm sand was deposited in Ganga in just five years from 2002 to 2007.”He also said: “Yamuna is a tributary of Ganga and the main river is always deeper than its tributaries but in Allahabad, Yamuna is deeper than Ganga due to less siltation.” Elements containig arsenic released by industries have also posed a serious threat to the self purification mechanism of Ganga from Balia to Kanpur, says the report. After going through the findings, the UGC is reportedly planning a bigger study on the issue.
