Uttarkashi Hydro Project Faces Critical Tunnel Leakage Inspection
In a significant development for Uttarakhand's power infrastructure, authorities are preparing a detailed technological intervention to address a long-standing leakage issue in the Maneri Bhali Phase-II hydroelectric project located in Uttarkashi district. A high-level team of technical experts will deploy a Remotely Operated Vehicle (ROV) into the problematic tunnel during the first week of February 2024, marking a crucial step toward resolving this persistent engineering challenge.
Persistent Problem in Gamrigad Area
The leakage specifically affects the Head Race Tunnel (HRT) of the 304 megawatt hydroelectric facility, with the most troublesome section located in the Gamrigad area of Dharasu. Despite multiple repair attempts over the years, this particular leakage point has remained unresolved, continuing to discharge approximately 1,500 litres of water per second from the tunnel system.
The problem traces back to the project's construction phase in 2008, when engineers detected leakage at multiple points along the approximately 16-kilometre-long tunnel stretching from Joshiyara to Dharasu. While initial repairs allowed the project to be commissioned successfully, the leakage near Gamrigad area in Chinyalisaur block persisted, creating ongoing operational and safety concerns.
Previous Repair Efforts and Consequences
Historical reports indicate that in 2021, heavy leakage near the Margao-Chamyari section caused substantial damage to part of the Margao irrigation canal in Chinyalisaur block. This incident significantly disrupted water supply for local farmers who depend on this irrigation infrastructure for their agricultural activities.
The corporation responsible for the project undertook phased repairs using specialized grouting techniques, spending over Rs 3 crore to treat the leakage issue. Despite these substantial financial investments and technical efforts, the tunnel continues to leak at a concerning rate, raising questions about both the structural integrity of the hydroelectric project and the stability of surrounding land areas.
ROV Inspection Plan Details
The upcoming inspection operation will see the ROV enter the tunnel from the Dharasu Power House and travel approximately three kilometres toward Uttarkashi to specifically examine the problematic Gamrigad section. This advanced underwater vehicle will capture high-quality images and video footage of the affected tunnel sections, providing engineers with unprecedented visual data about the leakage points and surrounding structural conditions.
To facilitate this inspection, power generation from the facility will be temporarily halted for one to one-and-a-half days, demonstrating the seriousness with which authorities are approaching this leakage issue. The inspection team will comprise specialists from multiple organizations including the National Hydroelectric Power Corporation, the irrigation department, and Tehri Hydro Development Corporation Limited.
Expert Analysis and Future Planning
Vimal Dabral, Public Relations Officer of the hydropower corporation, confirmed that the expert committee will utilize the ROV's findings to formulate a comprehensive plan for effectively treating the tunnel leakage. This represents a systematic approach to a problem that has plagued the project for over fifteen years since its initial construction.
The persistent nature of this leakage highlights the complex engineering challenges associated with large-scale hydroelectric projects in mountainous regions. The upcoming ROV inspection represents a technological advancement in how such infrastructure problems are diagnosed, potentially setting a precedent for similar issues in other hydroelectric facilities across the Himalayan region.
