# Mamallan Reservoir project dispute in Tamil Nadu

> Live situation record from CLSTR: https://clstr.news/situations/mamallan-reservoir-project-dispute-in-tamil-nadu
> Updated: 2026-08-23T05:11:38.000Z. Sources: 2. Developments: 2.

In July 2026, approximately 30 youth organizations in Chennai organized a ‘March for Marshlands’ to protest the proposed Mamallan Reservoir. Demonstrators argued that the project would destroy vital tidal marshes, damage the ecosystem by blocking the Buckingham Canal, and negatively impact marginalized groups, including fishing communities and Dalits. Organizers called for an independent scientific review and urged the Tamil Nadu government to reconsider the plan.

By August 2026, the project faced administrative disputes as reports emerged that construction had proceeded without a required No Objection Certificate from the Fisheries Department. While the Water Resources Department has already completed roughly 30 percent of the 5,161-acre reservoir, the Fisheries Department has withheld approval. The department cited a need for further data to evaluate the impact on the environment and the livelihoods of an estimated 5,000 fishing families.

## Claims

- Approximately 30 percent of the construction work for the Mamallan reservoir has been completed. (corroborated by 2 sources)
- The Fisheries Department requires additional information to assess potential environmental and livelihood impacts. (corroborated by 2 sources)
- The project could impact the livelihoods of approximately 5,000 fishing families. (corroborated by 2 sources)
- The reservoir is designed with an annual storage capacity of 2.25 thousand million cubic feet. (corroborated by 2 sources)
- The Water Resources Department formally requested an NOC from the Fisheries Department on July 21. (corroborated by 2 sources)

## Timeline

### 2026-08-23: Mamallan Reservoir project faces dispute over missing fisheries clearance

The Tamil Nadu Water Resources Department is facing scrutiny for advancing the Mamallan Reservoir project without required clearance from the Fisheries Department, potentially impacting 5,000 fishing families.

2 sources. https://clstr.news/cluster/mamallan-reservoir-project-faces-dispute-over-missing-fisheries-clearance

### 2026-07-25: Chennai youth march against Mamallan Reservoir project

About 30 Chennai youth groups marched on July 25, urging Tamil Nadu authorities to halt the Mamallan Reservoir, citing wetland damage and threats to fishing and marginalised communities.

2 sources. https://clstr.news/cluster/chennai-youth-march-against-mamallan-reservoir-project

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Cite as: Mamallan Reservoir project dispute in Tamil Nadu. CLSTR, https://clstr.news/situations/mamallan-reservoir-project-dispute-in-tamil-nadu