The World Commission on Dams (WCD) has announced that the Government of Pakistan has agreed to support the WCD’s independent study of the country’s Tarbela Dam and the Indus river irrigation system, the world’s largest integrated irrigation scheme. This is the first of up to ten such case studies of dams in major river basins to be undertaken by the Commission in preparation of its June 2000 final report on the global experience in large-scale dams.

The Indus was an obvious choice as a case study, covering an area of about 1M km2, with more than 150M people living in the Indus basin and its five main tributaries, the Jehelum, Chenab, Ravi, Beas and Sutlej. The irrigation system provides water to about 60% of Pakistan’s 20M ha of cultivable land in an otherwise arid to semi-arid region.

Tarbela dam, located on the Indus, is one of the world’s 45,000 large dams. It is 143m high, has a storage capacity of 11.9B m3 of water and a generating capacity of 3478MW. As with many dams, siltation is emerging as a major problem in the Tarbela reservoir. The dam was completed in 1976 and required the acquisition of 34,000ha of land and 20,000 houses. At least 80,000 people required resettlement as a result.

WCD’s case studies intend to give ample attention to the views of non-governmental organisations involved in social and environmental aspects of river basin management; to small-scale as well as large-scale farmers, to hydrologists, engineers and utilities; and to people living both upstream and downstream of existing dams.

Along with the eight to ten in-depth case studies, the WCD Secretariat will also undertake a more limited analysis of an additional 150 dams, primarily using existing data available from a wide variety of sources.

Interested parties can contribute to the Commission’s deliberations by making submissions to the WCD and through the series of consultations the Commission will hold in the next several months.