Road across Yamuna will harm river, trigger flood: Experts

The illegal road across the Yamuna constricting its flow could not only play havoc with the river’s ecology but also inundate the river’s banks threatening human settlements in the future, experts have warned.

Ecologists said the blockage would upset natural activities such as silt transportation, groundwater recharge and revival of subsoil bacteria.

“Flowing water is the main factor that makes river ecology different from other water ecosystems. This is known as a lotic (flowing water) system. If that is stopped, the ecology of the river would be affected,” said CR Babu, ecologist.

He said as the water flow is partially blocked the river would start depositing the silt on its own bed. This would further decrease the depth of the river and it would become shallow.

“A river, if blocked, would be unable to flow freely. It would in turn inundate the flood banks,” said Sushmita Sengupta, manager water programme of Centre for Science and Environment.

Experts claimed that as the Yamuna is already highly polluted, blocking its flow further would tantamount to increasing the pollution load further. This could contaminate the groundwater and aquifers, which the river used to recharge.

“If the river fails to flush down the pollution load, it would start getting concentrated in the stream. Ultimately, this would reach the aquifers. So we are heading for another disaster unless the blockage is removed at the earliest,” said Shashank Shekhar, who teaches geology in Delhi University.

Allegations have already surfaced that the road was constructed by sand mafia which used to excavate sand from the islands in the river. DDA had earlier stumbled upon a large ditch in the riverine island from where sand had been dug out.

“Even though it won’t affect much the river’s hydrology, it would disturb the biodiversity that has evolved in that island. A lot of animals take shelter in such islands such as birds and aquatic organisms. They would be disturbed,” said Shekhar.