The Expert Appraisal Committee (EAC) of the Union Environment Ministry has deferred the grant of Terms of Reference (ToR) for the proposed ₹1,875-crore Koraiyar reservoir project in Tirunelveli district and directed the Water Resources Department (WRD) to examine alternative sites outside the Kalakkad Mundanthurai Tiger Reserve (KMTR).
The proposal, discussed at a recent meeting, involves the construction of a reservoir across the Koraiyar at Vickramasingapuram in Ambasamudram taluk to irrigate a cultural command area of 9,091.5 hectares (ha). The project is intended to harness monsoon flood flows from the Koraiyar, a tributary of the Tamirabharani, for irrigation, flood moderation, and groundwater recharge.
The proposed reservoir will have a dam height of 43 metres and requires about 16.95 kilolitres of water a day during construction. The project has been classified as a Category A proposal for environmental appraisal because it falls within the tiger reserve, even though its command area would otherwise place it under the Category B1.
According to the project proponent, the reservoir would increase the irrigated ayacut from the existing 1,225.66 ha to 9,091.5 ha, benefiting drought-prone areas in Alangulam, Manur and Tirunelveli taluks, where farmers have sought assured irrigation. The project is also expected to stabilise existing irrigation, improve groundwater recharge, and reduce downstream flooding.
However, the committee raised concern over the project’s ecological implications as it falls within KMTR, which is a protected area of high ecological significance supporting tigers, Nilgiri langurs, and other endemic flora and fauna. The EAC observed that the project would require 819.21 ha of land, including 186.74 ha of forest land and 632.48 ha of non-forest land. The submergence area would cover 278.11 ha, including 156.44 ha of reserve forest. It also said the project proponent had not yet applied for Stage-I forest clearance.
The committee further said the project proponent had not adequately examined alternative options to achieve the proposed irrigation benefits. It suggested exploring reservoir sites in the headwaters of the Chittar basin to augment the capacity of the Manur and Pallamadai tanks, saying such alternatives could meet the intended objectives with lower investment and reduced environmental impacts.
During the deliberations, the committee also recommended examining the possibility of relocating the proposed dam to other undammed tributaries of the Chittar river basin outside the tiger reserve, which it said could substantially reduce the impact on wildlife habitats and protected ecosystems.
Deferring the proposal, the EAC directed the WRD to submit a comprehensive analysis of alternatives, covering different project locations, configurations and designs, supported by site-specific studies, maps, and technical, ecological, and economic comparisons. It also sought a detailed justification for locating the project within the tiger reserve, including an assessment of likely impacts on tiger habitats and other ecologically important species.
Published - July 11, 2026 06:31 pm IST