Page 12 - VIPNET Curiosity Mar 21

Use of Drones in Rapid Assessment of Sand Mining and Its Impact on the Ganga River
Peeyush Gupta
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Map: Sand Mining Sites in Ganga Basin
by sand mining and unsustainable sand mining has been rampant despite the 2016 guidelines issued by the Ministry of Environment and Forests. To strengthen the existing system and to curb the illegal and
March 2021
and mining has emerged
as a major global issue
and the indiscriminate extraction of river sand and
gravel is manifold higher than natural replenishments in several river basins across the world which can impart serious offsite and onsite impacts.
This ultimately leads to changes in channel form, physical habitats, food webs and engineering structures associated with river channels and its watershed. As these adverse effects become increasingly recognized and understood, in-stream sand mining/ aggregate extraction has invited increasing scientific scrutiny. Although more focused research leading to restoration of river environments
are needed, but it is amply clear that large-scale mining of sand, gravel and stones from riverbeds and banks alters the natural flow of a river and may severely affect the entire river system. At the same time, the Himalayan
rivers are known for exceptionally high sediment flux, and several reaches are also anthropogenically modified due to several interventions such as barrages and bridges which influence the natural flow regime and hence sediment transport. Therefore, the identification of reaches of excessive sedimentation
is equally important because this
can lead to serious problems of river management including river-related hazards. It is important to maintain
a balance among sediment supply, effective transport, and sedimentation. Any deviation from this may lead to major changes in river morphology and
processes. It is critical to understand these issues before drafting a long-term policy for sand mining in the Ganga basin.
Several rivers draining the Ganga basin are severely impacted