Construction Dewatering for Underground Station in Urban Environment

Abstract

Metro is seen as the only solution for mass rapid transit system in the urban areas. For an underground metro station, deep excavations in densely populated areas impose specific challenges to the contractor. Based on the type of soil or rock, excavation procedure, method, and time shall be adopted. The control of groundwater is one of the most common and complicated problems encountered on a deep excavation. The contractor selects the dewatering method, and the contractor is solely responsible for its design and operation. Many dewatering techniques like multiple wells, sump pumps, vacuum pumps, and deep wells are available to control groundwater. In this paper, the author explains the usage of MODFLOW software for dewatering analysis in the underground metro station and also about the dewatering system which has been adopted in the site. Pump out test is an accurate method of determining the safe yield of the well and also for assessing the actual site condition.