Steered drilling for waterpipes according to a new system

Abstract: The residents on Lövängsvägen in Kimstad have had problems with waterleakage since early 1970. Norrköping Vatten decided, after many reparations on the drinking water and sewagesystem, to finally change the main pipeline that provides the 24 households with fresh water. To dig up the approximately 400 meter of street with belonging valves would be an extensive project that would result in many forms of disturbances such as access to water and pass ability for the inhabitants on Lövängsvägen. The method that was applied came to be a new patented method presented by Brimer AB by the name Briband. Briband means that steered drilling, a shaftless method to change water pipes, can be used in combination with new wells with preinstalled valves. Through this performance the disturbances could be avoided and the installation procedure faster. We have compared the Briband system with the conventional method technically to differentiate them. But it is not possible to generally decide which is best since both methods have advantages and disadvantages. However, steered drilling has an environmental advantage because of less transportation needs of soil masses, to and from the construction area. An advantage of having many of the valves collected in a well is that future needs for digging the street up just to reach them, will be eliminated. There will also be the option to cut off the water supply for parts of the street during handling and maintenance, and in this way avoid affecting more than 6 households at the same time. The new wells with belonging valves can be preordered according to the customers needs. The wells are also of closed type, which means that they will easily flood if a leakage would occur. But with preinstalled alarming system in the wells such leakages can be identified. Norrköping Vatten and Stadspartner who will operate and maintain the new system, hope that the future costs in form of control and reparations will decrease compared to the existing system. The ground in Kimstad consists of clay and silt, which with present drill equipment is the right condition to perform steered drilling. Since digging is not needed, the method saves money in form of restoration-costs. An economic calculation of how much it would have cost to accomplish the project through the conventional method has been made. Later we used the calculations to perform a financial comparison between the two methods. Some problems occurred during the project that complicated the process and caused increased expenses. A leakage that came up in relations to the drilling and line pulling was the incident that cost the most, because the leakage led to additional work in form of shafting parts of the street that otherwise would have remained untouched. The total cost for the project ended up a little more that the predicted sum but still considerably less then to perform the project by using the conventional method. The steered drilling was regardless the disturbances that came up during the project, thanks to the areas land condition, the most ultimate method considering the circumstances, both financially and technically. The shaft-less method also gave benefits in terms of time, despite the problems. The interviews with the locals also showed that this method was the most suitable since their experiences of the problems were insignificant and since they were pleased by the work performance in total.