New Delhi – A major controversy has erupted over the definition of the Aravalli Hills, following the Supreme Court’s acceptance on November 20 of a recommendation from a Union Environment Ministry panel that critics warn will strip protective legal cover from the vast majority of the mountain range. This redefinition, though ostensibly intended to regulate mining, is feared to open up over 90% of the Aravalli landforms to potential destruction from quarrying and construction, with severe environmental ramifications for the National Capital Region (NCR).
The accepted definition classifies any landform as part of the Aravalli Hills only if it has an elevation of 100 meters or more above the local relief, along with its slopes and adjacent land.
Forest Survey of India Critical Warning
What the Environment Ministry panel did not explicitly highlight is the drastic consequence of this 100 meter threshold. An internal assessment by the Forest Survey of India FSI found that barely 8.7% of the 12,081 Aravalli hillocks those 20 meters or higher) across 15 districts in Rajasthan would meet the 100 meter criterion.
The FSI and environmental experts had previously red-flagged the importance of the lower hills and shorter ridges, many of which fall below the new 100 meter cutoff. These lower landforms are crucial natural barriers that prevent sand and dust from the Thar desert from flowing eastwards into the plains of Haryana, Delhi-NCR, and Western Uttar Pradesh. By removing protection from these shorter but vital hillocks, experts warn that the ecological continuity of the Aravallis will be broken, significantly worsening dust pollution and air quality in the NCR.
Implications for Ecology and Development
Environmentalists and water conservationists have criticized the judgment, warning that the exclusion of low-elevation hills will expose vital ecological assets to mining and real estate expansion:
• Hydrological Risk: The Aravallis act as a critical groundwater recharge zone, with fractured rocks allowing significant water percolation. Disturbing these hills through mining could severely alter aquifer patterns and intensify water scarcity across the region.
• Climate & Biodiversity: The scrub-covered, low hills play a decisive role in moderating wind velocity, retaining moisture, and regulating local climate. Their loss risks shrinking wildlife habitats, including those for leopards and hyenas, and intensifying heat stress across northwest India.
While the ruling provides a uniform benchmark for states with Aravalli terrain Gujarat, Rajasthan, Haryana, and Delhi and does not immediately alter protections under existing laws like the Punjab Land Preservation Act or forest laws, activists fear that the \text{100}-meter elevation criterion, originally proposed by the mining department, will be used as a dangerous reference point for planning and real estate zoning, thereby accelerating the range’s degradation.
The government maintains that the Supreme Court appreciated the panel’s recommendations, but critics argue that the acceptance of this definition effectively removes the “green shield” from a majority of India’s oldest mountain range.