ISLAMABAD, Jan 1: The World Commission on Dams (WCD) says that large dams built round the globe have produced more disadvantages than benefits. It calls for trust building and consensus among all stakeholders before going for construction of big reservoirs to achieve maximum economic outcomes.

The WCD reached the conclusion in 2000 after analyzing the outcome of about 45,000 dams, country-specific studies and input of international community.

The Technical Committee on Water Resources led by A.N.G. Abbasi has recently reported that the WCD report had not been given ‘adequate consideration’ by Wapda and called for its adoption as a guideline for future reservoirs.

“Dams fundamentally alter rivers and the use of a natural resource, frequently entailing a reallocation of benefits from local riparian users to new groups of beneficiaries at a regional or national level,” said the WCD report.

People of Sindh have been saying that construction of large dams on Indus will deprive them of their rightful water share and benefit Punjab at their cost.

The WCD acknowledged that dams had made a significant contribution to human development, but pointed out that in too many cases an unacceptably higher price had been paid by displaced people, downstream communities and natural environment to secure those benefits.

It said the lack of equity in the distribution of benefits called into question the value of many dams in meeting water and energy development needs.

The commission advised the governments to keep in mind that shortfall in technical, financial and economic performance of such projects could cause significant social and environmental impacts and their costs would have to be borne by poor and indigenous people and other vulnerable groups.

Keeping in view of the huge capital involved in construction of big dams, the commission noted that substantive evaluations of such projects were few in number, narrow in scope and inadequately linked to decisions on operations.

It noted that large dams displayed a high degree of variability in delivering predicted water and electricity services and related social benefits with a considerable portion falling short of physical and economic targets.

Large dams have demonstrated a marked tendency towards schedule delays and significant cost overruns and have typically fallen short of recovering their costs.

Dams generally have a range of extensive impacts on rivers, watersheds and aquatic ecosystems; these impacts are more negative than positive and, in many cases, have led to irreversible loss of species and ecosystems.

It said the project planning and appraisal for large dams should not be confined to technical parameters and the narrow application of economic cost-benefit analyses and instead higher attention be given to social and environmental impacts.

The commission is of the opinion that all those should be brought to the table whose rights are involved so that conditions for finding a resolution of competing interests and conflicts could be created.

From the 1930s to the 1970s, the construction of large dams became synonymous with development and economic progress and this trend peaked in the 1970s when on average two or three large dams were commissioned each day somewhere in the world.

The report said many of the non-dam options available today, including demand-side management, supply efficiency and new supply options, could improve water and energy services.

It pointed out that a number of supply-side options at all scales (from small, distributed generation sources or localized water collection and water-recovery systems to regional-interconnection of power grids) could collectively improve the delivery of water and energy services in a timely, cost-effective and publicly acceptable manner.