After the resounding success of the Chukha Hydropower Plant and its socio-economic bearings on the people of Bhutan and India, the proposal for another hydropower plant in the Wangchu river basin was conceived and resulted in a pre-feasibility report prepared in 1983. Following the discussions held between His Majesty the Fourth King of Bhutan and the then Union Minister of Energy, GoI, in January 1990, a high-level expert term was deputed by GoI to reconnoitre the various Project areas in February 1990. The expert team indicated the prima-facie feasibility to two projects namely, the Tala Project and the Wangchu Reservoir Scheme and recommended that detailed studies be taken up. Thereafter, the two Governments entered into a Memorandum of Understanding on November 25, 1990, for carrying out detailed investigations and studies. The work was assigned by the MEA, GoI to M/s. Water and Power Consultancy Services (WAPCOS), an Undertaking of the Ministry of Water Resources,Government of India, vide an Agreement of February 18, 1991. In July 1991, WAPCOS initiated Site Surveys, Field Investigations and Studies relating to hydrology, meteorology, topography, geology, seismology, geophysical and geo-technical properties, quarries for construction materials and environmental aspects.

The Tala Project is located in Chhukha, Western Bhutan, just downstream of the Chhukha Project. Field investigation work related to the Tala Project was completed in March 1993. After finalizing of desk studies, a draft Detailed Project Report (DPR) was prepared by WAPCOS, on schedule, by August 1993. Various comments and suggestions on the draft DPR were received during a presentation of the draft DPR. A final DPR, incorporating these comments/suggestions, was prepared in October, 1993.

The Agreement for the implementation of the Tala Hydroelectric Project was signed by the two Governments on March 5, 1996, following which an autonomous body named the Tala Hydroelectric Project Authority (THPA) was constituted for the construction, operation, and maintenance of the Project.

WAPCOS was appointed as the engineering design Consultants to the Project Authority. The expertise of premier organizations of the GoI viz the Central Electricity Authority, Central Water Commission, Central Water & Power Research Station, Central Soil & Materials Research Station, Geological Survey of India and Survey of India were also made available to the Project through WAPCOS. The National Institute of Rock Mechanics (NIRM) still continues to provide consultancy in instrumentation in various appurtenants of the Project.

The implementation of the Project, including creation of basic infrastructural facilities started in October 1997. The main works of the Project started in early 1999. Despite many adverse geological problems encountered in many components of the Project and the extensive damages caused by the unprecedented rains of 2000, the first unit of the Project was commissioned on July 31, 2006, and the last unit was added on the bar on March 30, 2007. The Project components stretch for approximately 100 km from the Dam at Wangkha to TRT Outfall at Tabji.

Tala Hydropower Plant

To supplement power generation from THP during the lean season, Tsibjalumchhu stream, immediately on the downstream of THP dam on the left bank of Wangchhu river, was diverted to the dam on June 30, 2014. The diversion scheme, built at a cost of Nu. 285.760 million has the potential to augment annual energy generation by 93 MU, utilising the Tsibjalumchhu inflow during winter months. The augmentation project was fully undertaken by DGPC, including the feasibility studies, design and engineering.
From 2012 onwards, the original cast runners were replaced with forged fabricated runners and further hard-coated to withstand the pitting and abrasion by sediments.
The Computerised Controlled System (CCS) could not be made fully operational despite continuous efforts since the commissioning of the project. It is proposed to replace CCS by a modern SCADA system. Further, other initiatives as part of resolving teething problems and modernisation were also initiated.

The project has made significant contribution to Bhutanese economy. Upon commissioning, the GDP contribution of electricity sector increased from about 13% to about 20%. The availability of power also spurred the growth of many domestic industries in the country.
Even during the project construction phase, the local economy of Gedu went through a dramatic transformation as the project provided growth opportunities and made significant contributions. The project provided the community with better road access and other infrastructure such as water supply, and facilities like communication, schools and health services. Such assets built by the project authority have been handed to the various government agencies.
THP continues to provide many such services for the benefit of its employees and the community. THP has set up early child care and development centre, basic health unit, lhakhang and school for the benefit of its employees as well as the local community.

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