User's guide of Proceessing Modflow 5.0

Processing Modflow 275
6.5 Geotechniques
6.5.1 Inflow of Water into an Excavation Pit
Folder: \pm5\examples\geotechniques\geo1\
Overview of the Problem
Fig. 6.43 shows a plan view and a cross section through a shallow aquifer situated in a valley.
In the north the aquifer is bounded by the outcrop of the sediments in the valley, while the south
boundary is a river, which is in contact with the aquifer. The aquifer extends several kilometers
to the west and east, it is unconfined, homogeneous and isotropic. The top and bottom
elevations of the aquifer are 7 m and 0 m, respectively. The average horizontal hydraulic
conductivity of the sandy sediments is 0.001 m/s; the effective porosity is 0.15. The
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groundwater recharge from precipitation is 6×10 m /s/m . The water stage in the river is 5 m
above the flat aquifer bottom, which is the reference level for the simulation. At a distance of
200 m from the river there is an excavation pit. The length of the pit is 200 m, the width 100 m.
The bottom of the excavation is 3 m above the aquifer bottom.
Your task is to calculate the inflow into the pit and show head contours and catchment area
of the pit.
Fig. 6.43 Problem description
6.5.1 Inflow of Water into an Excavation Pit