WorldWide Drilling Resource

23 MAY 2022 WorldWide Drilling Resource® A Thousand Connections for Cochabamba Adapted from Information by TRACTO With about 631,000 inhabitants, Cochabamba is Bolivia's fourth largest city and the seat of a university. Located in the eastern Andes at 8398 feet above sea level, it is an ancient place with numerous ruins from the pre-Inca and Inca periods. Cochabamba made international headlines at the beginning of the millennium when citizens successfully fought against privatization of the drinking water supply in the so-called “water war.” Since then, water supply has been relatively secure, at least in north Cochabamba, which is nicknamed “Ciudad Jardín” (Garden City) because of its many parks and gardens. In south Cochabamba, however, there is still a water shortage because conduits do not reach there. Step by step, the Municipal Potable Water and Sewage Service (SEMAPA) is tackling the enormous task of bringing water to this area, and recently succeeded in significantly improving the water supply in the city center. The 20-mile-long, dilapidated drinking water network in this district was completely renovated, which also required building all-new house connections. Along with new supply lines, a total of 2758 house connections had to be built. InAvenidaAyacucho, an area where streets are relatively narrow and buildings are dense, SEMAPA chose to build approximately 1000 house connections without trenches using the GRUNDOMAT soil displacement hammer. The two-stroke thrust and movable head ensured the hammer’s targeting accuracy and penetrating power, even in stony soils, making it ideal for the fast and economical underground construction of house connections in Cochabamba. After excavating the necessary minimum start and target pits and aligning the machine to the target, the pneumatically-driven GRUNDOMAT 45 worked its way under the road at a depth of about two feet along the given path. The ground, consisting of clay with a sandy component, and the occasional groundwater horizon posed no problems for the installation. Even existing old drinking water and sewage pipes, as well as communication and gas pipes, could be passed under without damage. Installation time per house connection was 1 to 1½ hours each. New HDPE (highdensity polyethylene) drinking water pipes were pulled in during a second working step. By rebuilding this drinking water network, Cochabamba has secured its water supply for the long-term and improved living conditions for citizens. In addition, the use of trenchless technology was an effective way to make water connections in an economically and ecologically gentle manner. WTR