مخاوف حقيقية من انهيار وشيك لسد مروى

Quote: The German Swiss -US LAMI Consortium knew that the cavity filled limestone, heavily fissured volcanic rocks and active seismic faults along the middle Chixoy River provided a very unstable foundation for any large constructon project. Nevertheless, their 1974 feasibility study recommended that the Guatemalan electricity utility INDE should build a 130 meter high hydropower dam on the Chixoy at a place called Pueblo Viejo. In February 1976, with a $105 millions loan secured from the Inter-American Development Bank, construction of the dam was about to begin when a devastating earthquake hit Guatemala. Te quake prompted a more detailed review of the seismology of the site - which found several previously undetected aults - and of the seismic strength of the planned dam. A sebsequent redesign to make the dam better able to withstand earthquake delayed construction for 15 months an increased the estimated cost of the project by nearly 10 per cent. In May 1977, with further international loans secured, contractors from eight different countries finally started to build Chixoy dam. LAMI. [redictably, received the lucrative contract as consulting engineers to oversee the construction of the dam they had designed and recommended to built. Almost as soon as construction began it became apparent that it was not only LAMI's seismological investigations which had been inadequate; while preparing the dam foundations, the underlying rocks were found to be so riddled with faults and cavities that another major redesign of the dam was needed. this resulted in the final expenditure on the dam wall being 350 per cent higher than expected in 1977. Next, another undiscovered fault required design change that more than double the cost of Chixoy powerhouse. Finally, the 26 - kilomters long pressure tunnel intended to carry water from the reservoir to the powerhouse caved in twice during its excavation by German contractor Hochtief delaying project completion by some 14 months. Chixoy dam finally began to produce power in July 1983, but after only fivemonths further severe damage t the pressure tunnel forced INDE to shut the palnt down. The subseqent repairs took two years and cost some $57 millions, most of the money coming from a second loan from the World Bank. Commercial operation of Chixoy five 60MW turbines didnt resume until April 1986. In 1974 LAMI estimated that Chixoy would cost$ 270 million by1988 it had cost$944 millions.