New Delhi, March 23 -- The Delhi Jal Board (DJB) has approached the National Green Tribunal (NGT) seeking permission to operationalise over 100 borewells installed along the Yamuna floodplains, in the Capital's O-zone, an eco-sensitive area where construction is largely prohibited, aiming to augment water supply ahead of the peak summer months. However, with over 40% of Delhi's groundwater already "overexploited", experts warned against excessive reliance the process. "The proposal has been submitted to the NGT in compliance with environmental regulations governing groundwater extraction in the ecologically sensitive floodplain zone. We have installed more than 100 borewells in the O-zone and have sought permission from the NGT to start usi...