Mandated to carry out the task of supplying water to the burgeoning city, the Delhi Jal Board has now decided to join the ongoing campaign to protect the floodplains which are an important groundwater recharge source. It has suggested converting a portion of the floodplains at Palla into a sanctuary or a notified area to stave off encroachers and to develop it as a source of water for the city.
The water utility has decided to lend its support to the conservation efforts to save what remains of the Yamuna floodplains in the city, after being apprised of the importance of floodplains as a potential source of water for the city and its increasing population.
To begin with, the Jal Board wants immediate steps to be taken to notify the floodplains as a protected area and laws passed to ensure there is no violation through constructions or encroachment.
The DJB is already working on a project to tap the potential of the river banks as a source of water for the city and has installed over 90 tube-wells that are supplying water for about 25 lakh people on the floodplains at Palla. And it is keen that the conservation project takes off from there.
“Floodplains that are South of Wazirabad cannot be tapped because of heavy pollution in the river waters there. But North of Wazirabad, steps should be taken immediately so that they can be protected,” said DJB Chief Executive Officer Ramesh Negi.
Suggesting that the Delhi Development Authority should notify the floodplains at Palla as a protected zone, he said: “As of now the area where we are currently carrying out the project is under agricultural use, efforts should be made to reclaim this land, by either declaring it as a sanctuary or other legal means to conserve it and allow ground water recharge. There should also be continuous monitoring of that stretch.”
Prof. Vikram Soni, who is an advisor to the DJB and is part of the Palla project, said preliminary assessment from the study carried out along with Diwan Singh of NGO Natural Heritage First, Dr. S.V.N. Rao of WAPCOS, a consultancy and Dr. Shashank Shekhar of Delhi University suggests that the floodplain can be an effective source of groundwater in a non-invasive and inexpensive way.
“In future getting water for the city will be difficult as the sources are not many. So we began a project to examine the possibility of a sustainable water supply for Delhi from a local source -- the Yamuna floodplains. We are studying the sustainable water withdrawal from the extended floodplain sand aquifer that runs along the river, which is about two kilometres wide and about 40 metre deep and we have found that the floodplain is a perennial solution that can provide about a quarter of Delhi's water supply non-invasively,” he said.
The preliminary results of the study at Palla, which will be completed soon, indicate that the floodplain replenishes the water withdrawn in less than a day. “Tube-wells on the other hand, draw only 0.3 mgd a day. At present only about 50 of the 97 tube wells are operational. Once we refurbish the wells we can get a supply of 36 mgd. Importantly, this is essentially local and will preserve the ecological sanctity of the Yamuna and provide Delhi with good water valued at over Rs.3,000 crore a year at the value of commercial tanker rates, or 1 sq km of floodplain can yield a value of about Rs.50 crore a year,” explained Prof. Soni.
