Maintaining the river sand layers is very important in controlling the floods: expert
With sand quarries all over the State being shutdown for one reason or the other and the construction season gaining momentum, sand has become a scarce and precious commodity in the city. Those who want sand in small quantities have to pay up to Rs.30 a bag. They are paying not so much for the sand, but for the effort that goes into collecting it.
An individual or a small group of people collecting sand into empty cement bags from the Krishna River Bed and loading it on to a platform rickshaw is not an uncommon site, but people doing the same from canal beds is rare. Sand prospecting is not so popular in the canals because their beds are usually covered by slush. The municipal sewage being dumped into it at 52 points in the three canals that cut across the city is one factor that contributes to the formation of slush. Fortunately for the ‘sand prospectors” the water brought in some sand and deposited it in Ryves and Eluru Canals this year.
A group of sand prospectors made the best of the opportunity and began collecting sand from the canal. They are saved of a long tedious walk they have to take up if it was the river.
The Irrigation Department that is responsible for desilting is not always so lucky. If the canal water brought in sand every year the department would be happy because it could call for auctions in the canals too and sit back and enjoy while contractors do the ‘dirty work' of cleaning up.
While sand is still being used for construction the impact of sand mining in rivers had a negative impact, according to experts. National award winning geologist Nandipati Subba Rao in a paper said, “maintaining the river sand layers is very important in controlling the floods and also in avoiding the droughts, because the sand layers have the capacity to maintain absorbed water.”
When the rate of sand extraction exceeds the rate of natural replenishments of the sediments, there was severe damage to the “river basin environment,” he said. While alternatives have been found for sand in areas where it was very scarce the same should be done before irreparable damage was done to the river beds the consequences of which were still not completely understood.