Tools for Calculating the Radius of Influence, Pumping Rates and Times for Dewatered Excavations

Empirical methods can be used to calculate the radial extent of the groundwater cone of depression as well as the estimated pumping rates and times necessary to achieve the required groundwater drawdown for dewatered excavations.

Ground Support Systems provide a tool for conducting these calculations, based on these methods. However these results should not be solely dependant on, and further calculations should be made prior to any works commencing. 

Contact us today for a comprehensive dewatering design and analysis.

In the absence of site-specific hydraulic data, default hydraulic conductivity values (K) can be used and are listed below for a variety of Australian soil types.

  • In the absence of site-specific information, the saturated thickness of superficial aquifers may be obtained from: Perth Groundwater Atlas, Second Edition (Department of Environment, 2004) for sites in the Perth metropolitan region; and from information held by the Department of Water (for sites elsewhere in the State).

  • Adapted from Davidson, W.A., 1995, Bulletin 142: Hydrogeology and Groundwater Resources Of The Perth Region, Western Australia, Geological Survey Of Western Australia. 

  • Hemond,H.F. and Goldman, J.C., 1985, On non-Darcian water flow in peat. Journal of Ecology, 73, 578-584