Chapter 16: Groundwater flow

This chapter covers the fundamental principles of steady-state groundwater flow in a saturated soil, based on Darcy's Law and the concept of soil permeability or hydraulic conductivity. Simple flow regimes including radial flow to single wells are described, and the use of plane flownets in plan and cross-section to calculate flow rates and pore water pressures is discussed. Flow in strata of anisotropic permeability and across a boundary between two soils having different permeabilities is briefly considered. The importance of controlling pore water pressures in the vicinity of an excavation is illustrated with reference to a case study, and some common methods of groundwater control are summarised. Finally, the concepts of transient flow and consolidation are introduced.