By AN Mohammed, Consultant, NHPC Ltd and Manjusha Mishra, General Manager, Hydrology, NHPC Ltd
After the partition of India in August 1947, the use of the waters of the Indus and its tributaries became a major dispute between India and Pakistan. The Governments of India and Pakistan, being equally desirous of attaining the most complete and satisfactory utilization of the waters of Indus system of rivers, led to the signing of the Indus Water Treaty (IWT) that came into effect on 1 April 1960.
The Treaty was also signed by the International Bank for Reconstruction and Development in respect of the World Bank’s role under certain provisions of the Treaty. The Indus system of rivers comprises of the rivers “main Indus” and its tributaries Jhelum, Chenab, Ravi, Beas and Sutlej. As per the Treaty, Ravi, Beas and Sutlej which constitute the eastern rivers, were allocated for unrestricted use by India before they enter Pakistan. Similarly, Pakistan had unrestricted use of the western rivers – Jhelum, Chenab and Indus which India is under obligation to let flow under the provisions in the Treaty. Indus Water Treaty is the only international treaty that has been implemented over the last 62 years with sincerity by both India and Pakistan.
Provisions regarding the Eastern Rivers have been mainly dealt in Article II of the Indus Water Treaty which allows India to have unrestricted use of all the waters of the Eastern Rivers. For Pakistan, the provision is – “Except for domestic use and non–consumptive use, Pakistan shall be under an obligation to let flow and shall not permit any interference with the waters of the Sutlej Main and the Ravi Main in the reaches where these rivers flow in Pakistan and have not yet finally crossed into Pakistan.” Also, it mentions that “All the waters, while flowing in Pakistan, of any Tributary which, in its natural course, joins the Sutlej Main or the Ravi Main after these rivers have finally crossed into Pakistan shall be available for the unrestricted use of Pakistan.” Article IV states that – “Neither party will take any action which would have the effect of diverting the Ravi main between Madhopur and Lahore, or the Sutlej Main between Harike and Suleimanke, from its natural channel between high banks.”
In the same clause, it is stated that Pakistan shall construct and bring in operation a system of works which would accomplish the replacement of water supplies for irrigation canals in Pakistan which were dependent on Eastern Rivers on 15th August 1947.
Prior to the partition of India in August 1947, India had developed projects on Ravi and Beas river systems. The earliest project built was the Madhopur Headworks in 1859 to divert flows through the Upper Bari Doab Canal to provide 1821 million cubic meters (MCM) of water for irrigation in the command area of 3.35 lakh hectares (ha) of land in Gurdaspur, Amritsar and Lahore districts of pre-partitioned India. After independence, Bhakra Nangal Multipurpose project on the Sutlej River in Himachal Pradesh was constructed during 1948-1963. At the time of signing of the Indus Treaty, 3860 MCM of water from Ravi and Beas River system was used by major irrigation systems. After signing of Indus Water Treaty, in order to utilize water resources of Satluj, Beas and Ravi, number of large/ multipurpose projects such as Naptha Jhakri, Harike Barrage and Satluj Yamuna Link Canal on Satluj river, Pong, Pandoh on Beas River and Ranjit Sagar, Chamera-I, Shahpur Kandi on Ravi river were planned. The unused flow in the river system was planned to be developed by the four states of J&K, Patiala and East Punjab States Union (PEPSU), Punjab and Rajasthan. However, with the merger of PEPSU with Punjab and subsequent bifurcation of Punjab creating Haryana, a dispute arose on the allocation of Ravi and Beas waters for which a tribunal was set up under the Interstate River Water Disputes Act. As per an agreement on 31 December 1981, based on mean annual flows of 21179 MCM water was allocated to Punjab 5205, Haryana 4317, Rajasthan 10608, Delhi Water Supply 247 and Jammu & Kashmir 802 MCM.
The Indira Gandhi Canal (originally, Rajasthan Canal), which is the longest canal in India (650 Km). It starts at the Harike Barrage, a few kilometres downstream of confluence of the Satluj and Beas rivers in Punjab and ends in irrigation facilities in the Thar Desert in Rajasthan. Construction of the canal started in 1952 and completed in 2010. It is a gigantic canal project to carry 524 cum/sec water from the Harike Barrage in Punjab, to the vast Greater Indian Desert known as the Thar Desert, in Western Rajasthan. The canal network is spread in an area of about 60 km wide and 1,000 km long belt. It consists of feeder of 204 km, main canal of 450 Km, 8000 km of distribution networks and several thousand km of lined water courses. It spreads over a gross command area of 25 lakh ha and provide irrigation to a culturable command area of 15.5 lakh ha. Sutlej Yamuna Link (SYL) Canal, about 121 km in Punjab and 90 km in Haryana envisaged conveying 4255 MCM out of 4317 MCM of Haryana’s average annual share of surplus Ravi-Beas waters. It would irrigate an area of 4.46 lakh ha in Haryana and also benefit Punjab in terms of irrigation to an area of 1.28 lakh ha and 50 MW of power generation. After completion of 85%, the works stopped due to dispute between Punjab and Haryana.
The Ravi river, known as Iravati in Vedic era, a transboundary river of India and Pakistan is the left bank tributary of Chenab which thereafter joins the main Indus in Pakistan. The river Ravi originates from Bara-Bhangal (near Rohthang Pass) at an elevation of 4229 m above mean sea level, approximately 80 Km North East of historical town of Chamba and flows in steep gradient with a series of loops and bends. The river Ravi is formed by combined waters of Kalihan, Budhil and Tundah Nallahs. The snow-fed river flows in a North-Westerly direction for most of its course through a narrow gorge up to Chitrari where after the valley comparatively opens out. Further it enters Punjab plains near Madhopur close to Pathankot. It then flows along the Indo–Pak border for 80 kilometres before entering Pakistan. With major tributaries are Baira, Siul and Ujh rivers, total length of the river is about 870 kilometres having catchment area of 13710 square kilometres in India. Within India, the river is under the jurisdiction of the riparian states of Punjab and Himachal and non-riparian states of Haryana, Jammu & Kashmir (J&K) and Rajasthan. The average annual flow in India up to the final crossing point in Pakistan is 7894 MCM.
The hydropower potential of the Ravi river system had been assessed as 3229 MW out of which 2177 MW have already been tapped by constructing fair number of water resources projects by the concerning State Governments, State and Central PSUs and private developers. There are 7 dams, 3 barrages, 1 weir, 2 lift irrigation schemes and 9 power houses in Ravi Basin. Himachal Pradesh has four hydro power projects namely 180 MW Baira Siul, 540 MW Chamera I, 300 MW Chamera II, 231 MW Chamera III. 120 MW Sewa II on Sewa river, 600 MW Ranjit Sagar (Thein) Dam on Ravi river fall in Kathua district of J&K. 206 MW Shahpur Kandi Dam on Ravi river comes in Gurdaspur district of Punjab. Sewa-III and Ujh Level Crossing Barrage are in Kathua District of J&K. Madhopur Barrage is situated in Gurdaspur district of Punjab.
Ranjit Sagar (Thein) Dam is the major multipurpose project for irrigation and hydropower built on the Ravi river. It is located 24 kilometres upstream of Madhopur Headworks built during pre-partition time. The left bank is in Punjab and the right bank is in Jammu. Government of Punjab constructed and commissioned the project in 1999. The project has a 160-metre-high and 617 m long earth gravel shell dam with a gross storage of 3280 MCM. Gross irrigation potential of 3.48 lakh ha of land and power generation of 600 MW (4×150 MW).
NHPC Ltd. has significant presence in Ravi Basin with 5 operating Power Stations in the basin. Baira Siul, Chamera-I, Chamera-II, Chamera-III in Chamba District, Himachal Pradesh and Sewa-II in Kathua District, J&K. Baira Siul Power Station in Chamba district, Himachal Pradesh is the first commissioned project of NHPC Ltd, a major step towards harnessing hydroelectric potential in Ravi river system. It utilized the combined inflow of three tributaries namely Baira, Siul and Bhaledh for generation of power on run-of-the-river basis. Since the power station had completed its useful life, renovation and modernization of the Power station was taken up by NHPC Ltd in the year 2019 for life extension of the project for another 25 years.
| Power Station | Installed Capacity (MW) | Commissioning Year | Dam Type/Height (m) | Design annual energy (Million Units, MU) |
| BairaSiul | 180 | 1981 | Earth core Rockfill Dam / 53m | 779 |
| Chamera-I | 540 | 1994 | Concrete arch gravity/ 120m | 1665 |
| Chamera-II | 300 | 2004 | Concrete gravity/ 43m | 1500 |
| Chamera-III | 231 | 2012 | Concrete gravity/ 55m | 1108 |
| Sewa-II | 120 | 2010 | Concrete gravity/ 53m | 534 |
Main features of the NHPC Ltd power stations on Ravi river
Chamera-II and Chamera-III are in cascade on main Ravi which operate in coordination as per the well-established mechanism of tandem flushing and peaking. Early Warning System (EWS) implemented in all the projects of NHPC. It encompasses establishment of automated upstream Gauge & Discharge (G&D) sites with Automatic Water Level Recorder (AWLR), real time transmission of data and 24×7 monitoring at its Master Control Room. Any untoward incident or unusual increase in water level upstream of dam is reported with sufficient lead time for timely action ensuring safety and security of downstream population. Disaster Management Plan and SOP on the “Adopting Measures for Protection of People Living in Downstream Area for Emergency such as Sudden Release of Water from Dam” stands implemented for each project. As per the latest National Green Tribunal (NGT) orders, the release of environmental flow from dams is ensured in all the NHPC Ltd. projects for sustenance of aquatic environment and downstream usage in the rivers. Design energy from NHPC Ltd. projects on Ravi river is 5586 MU. The beneficiary states/UTs of the power stations are Uttarakhand, UP, Delhi, Himachal Pradesh, Haryana, J&K, Punjab, Rajasthan and Chandigarh. The projects in the remote areas of Himachal Pradesh/J&K have brought all round developments, elevated the living standards of the local people with the rapid development in education, health, socio-economic, tourism sectors.