New Delhi: Delhi Master Plan 2047, passed by Delhi Development Authority (DDA) Wednesday, has once again brought into focus the controversial division of Yamuna floodplain into two parts.The plan has been passed and sent to Centre even as the National Green Tribunal (NGT)-ordered scientific determination and demarcation of the outer boundary of the floodplain is incomplete.NGT had given DDA time till this July 31 to demarcate the 1-in-100-year flood zone, but the agency on July 15 sought additional time to complete the exercise.The new master plan creates its own regulatory framework for the same vulnerable landscape, proposing recreational facilities, including a 52-km cycle track, in O-Zone II.DDA, as it had done in its draft MPD-41, has divided the 9,934-hectare ecologically sensitive Yamuna O-Zone into two parts — Zone I, covering the 6,295-hectare riverbed and one-in-25-year floodplain, and Zone II, comprising the outer, one-in-100-year floodplain, sources said.The one-in-100-year floodplain has a 1% chance of being flooded in any given year. The one-in-25-year floodplain has a 4% chance of being flooded in any year.When approached, DDA refused to comment on the issue, stating that the plan is yet to be approved by Centre.The tribunal, hearing matters concerning the 22-km Yamuna stretch from Wazirabad to Palla, directed the authorities in Delhi to demarcate the floodplain using the 1-in-100-year flood level along with one-metre contours.The contradiction becomes sharper because the 2047 plan’s division follows the approach that had already attracted scientific criticism in the earlier draft.In 2023, after the Yamuna reached a record 208.66 metres, TOI reported that DDA had proposed zero tolerance for construction in O-Zone I while permitting regulated development in O-Zone II. In its present form, O-Zone II constitutes about 35% of O-Zone and is already substantially encroached upon as, despite a complete ban on construction earlier, several encroachments have come up on the active floodplain over the years.Senior officials and experts have questioned the scientific basis of the zonal demarcation and argued that activities should be restricted across the entire floodplain.“First, unless they demarcate it, they cannot know which areas are within the 25-year- and the 100-year flood impact zones. For the 100-year demarcation, the embankments must be removed,” said an official requesting anonymity.Several ecologists, too, said they were not consulted on the decision regarding the floodplain.“Centre should not approve this proposal as it would legitimise encroachments in one of Delhi’s most ecologically sensitive areas. It would further dilute the already weakened O-Zone provisions and set a dangerous precedent for floodplain governance across the country,” said Bhim Singh Rawat of South Asia Network on Dams, Rivers and People (SANDRP).NGT’s current exercise is not based merely on DDA’s existing planning. The tribunal has specifically required the 1-in-100-year floodplain to be delineated with one-metre contours. However, the demarcation is pending and so is its final determination on the matter that it will hear next on Sept 13.There is also growing scientific evidence that the river has far less room to absorb extreme flows than it once did. A recent study by researchers from Delhi University and IISER-Bhopal found that Yamuna’s average width through Delhi has shrunk by nearly 68% between 1799 and today, while its estimated discharge fell by 89%.The researchers estimated that roughly one-third of Delhi’s floodplain has become disconnected over the past century because of embankments and urban development.
