Bolivia Inaugurates Misicuni TunnelThe 19.5 km trans-Andean tunnel to transport water from the Misicuni river in the Andes mountain range in Bolivia, the world's most infamous and slowest tunnel, was finally inaugurated on 16th April, 2005 more than 45 years after the project was first started, surviving wars, elections, civil insurrection, lack of financing and contractual disputes between several teams of contractors and the client Empresa Misicuni. The project with over a kilometre of cover faced endless difficulties throughout tunnelling with great rock pressure and squeezing ground, constant fallout, flooding, etc. After a JV of Condotte and Cosapi failed to complete the job within schedule, Italian-Bolivian consortium Astaldi-ICE Ingenieros was awarded a new contract in November 1997. Crews were doing better than 800 m a month in December 2001 but in January 2002, Astaldi-ICE decided to quit with only 500 m still to go. Two hard rock TBMs were used on the job, the first at Bocatoma was owned by Stadkraft and the second at Calio owned by ICE. On 21st February, 2002, Empresa Misicuni cancelled the contract and decided to take over the project to finish the tunnel on its own, maybe a world's first, commissioning the last portion to Robbins and paying a rent for the TBM owned by ICE. The tunnel holed through completely on 6th July, 2002. Astaldi-ICE started the final lining works of the tunnel in July 2003. Tunnelling and primary lining works were executed from three drives in Calio, Bocatoma and an intermediate shaft. Shotcrete support was installed by means of Aliva concrete pumps and a sprayer in thicknesses ranging from 5 to 25 cm, in accordance with the ground type encountered throughout the excavation of the 19.5 km tunnel. The tunnel was built by conventional means (about 840 m at Calio and about a total of 1.3 km at Bocatoma) and mainly with two hard rock TBMs. The cross section is horseshoe-shaped with a 4 m diameter when conventional means were used and circular (3.5 m in diameter) when the TBM was used. The scheme had a cost of USD87 million, financed by the Andean Development Corporation (CAF), the Bolivian government and the Italian government. Visit www.robbinstbm.comWith the Misicuni transfer tunnel, Cochabamba city's water and wastewater utility Semapa manages a bigger volume of water, from 950 to 1.350 litres per second. The municipal company pledged to distribute water 24 hours a day to the populations of the old city as well as the north, central and south districts. Water shortage is expected to be eliminated. The water began to flow once the valves were open at the Bocatoma portal. The water then flows in the tunnel towards Calio. Subsequently, a pipeline transfer the water to Mal Paso torrent, passing through Molle Molle, to finally arrive through another pipeline nearly 6 km long to Saloneo chamber built by Semapa in Tiquipaya. From Saloneo chamber, the water is transferred to Cala Cala treatment plant prior to becoming potable water from the faucet for the population. Click here to see a map of the route.The project has been split up in phases (drinking water, irrigation for farming in the Cochabamba valley and production of hydroelectric power). The main tunnel is the first phase. The remaining works represent a total of approximately USD130 million. The government estimates that all the financial resources will be found by 2007. The lack of finance for the two remaining phases of the project amounts to USD40 million. Contracts would be awarded the same year and construction would be finalised around 2011. The second phase includes rising the dam to 120 m; extending the hydroelectric power station to 120 MW and the surge tank; extending the drinking water treatment plant; constructing the 4.5 km east irrigation canal and extending the west canal to 18.5 km. The third phase will require the construction of 20 km of water tunnels in Putucuni and Vizcachas water basins; the extension of the surge dam; the extension of the treatment plant and the extension of the Mole Mole Red Media water pipe. Click here to read about the Calio drive superintendent telling about his experience at Misicuni. Subscribe to E-News Weekly 29/2002, 27/2002, 23/2002, 20/2002 & 9/2002. Click bo/11. 19/05.