Thursday, December 20, 2007

THE CASE AGAINST KALABAGH DAM





The Kalabagh Dam project comes at an important confluence of events. It reflects a crisis of governance, where decision-makers are at odds with an increasingly vocal society. Among other things, this stems from a concern that Kalabagh could trigger irreversible degradation of the Indus River Ecosystem. Also, the global and regional context for assessing large dams like Kalabagh is changing, with conventionally described irrigation, flood control and energy benefits being viewed through the prism of sustainable development.
The key imperatives, transparency and good governance, were never a factor in the formulation of the project. Thus, the technical specifications have undergone numerous revisions because of perceived concerns in the NWFP regarding seepage and inundation of surrounding areas, a problem that could have been resolved had affective communities been consulted. Politically, the dam has been a non-starter as its benefits are viewed as accruing to the Punjab, at the expense of Sindh and the NWFP, with both provinces the victims of water deprivation, ecosystem degradation and social displacement. The arbitrary manner in which the Punjab has appropriated water from the Indus River Basin in the past does not set a precedent for credibility. The issue of resettlement and rehabilitation is a contentious one, as there is outright mistrust of the government’s offer of compensation. Finally, increasing cost over-runs and mounting donor reluctance to finance a large and environmentally controversial project of this nature, give the lie to the government resolve to press on with building the dam; in particular, the government’s present fiscal insolvency precludes an investment of this magnitude.
Alternative to Kalabagh Dam
The proposed Tarbela Action Plan is based on computer simulations of sediment flows. These simulations were designed to: a) determine whether flushing was technically feasible and could be used to estimate storage capacity that could be sustained in the long run and; b) to analyze reservoir survey results and predict future sedimentation. Based on the simulations, three phased components of the action plan are proposed:
Reservoir Operating Strategy: Raise the minimum reservoir level to 1,365 feet by the year 1998 and by 4 feet each year thereafter.Second, limit the drawdown period to a maximum of 15 days. This would ensure security of power tunnel intakes for the next 10 years, long enough to complete construction of the underwater rockfill dike, and minimize the inevitable reduction in live storage.
Underwater Dike: Construct a rockfill underwater dike to protect the intakes of tunnels 1 – 4 from inundation by sediments.The dike would require some 8 Mcm of rockfill, have a crest level of 1380 feet, with an overspill section at 1340 feet.
Flushing Bypass: Construct a low-level high-capacity bypass to flush sediments.This should be on the left abutment, between the main and auxiliary spillways. Flushing should be carried out over a 30-day period.
The implementation of this plan would ensure long term and sustainable storage with only a small annual reduction in capacity.The estimated retention at 6 MAF is exactly what Kalabagh is designed to hold.However, flushing would reduce energy benefits because reservoir levels would need to be held down in June and July. On the other hand, the long-term energy producing potential of Ghazi Barotha clearly depends on Tarbela not silting up. Abstracting from social and environmental considerations, purely financial and economic cost comparisons also unequivocally favor Tarbela rehabilitation over Kalabagh.
To recap,Kalabagh dam is not the clear winner it is projected to be. First, its viability is premised on water availability figures that are highly questionable.Second, the land constraint precludes substantive increases in cultivable area, additional water notwithstanding.Third, crop yield increases based on additional water do not account for the aggravated water logging and salinity that would result; furthermore, higher doses of water are associated with high input use, which degrades both soil, and water quality.Using existing water more efficiently is clearly a better option on both environmental and equity grounds. Fourth, hydel energy is not unequivocally cheaper, given the growing propensity to factor in displacement and environmental costs. Also, borrowing costs are likely to be higher as donors have indicated a clear preference for thermal power projects. Fifth, Kalabagh would further exacerbate ecosystem degradation, adding to mangrove and species loss and impoverishing communities, which depend on the ecosystem’s resources.Also, as an instrument of flood control Kalabagh is poorly supported by the historical evidence.In view of these facts, the option of implementing a sedimentation management project on Tarbela appears a clear winner on all grounds – financial, economic, social and environmental.

No comments: