MWell

Version 3.3

Design of dewatering with well-point drainage and monitoring

MWell is an analytical calculation program for groundwater modeling to analyze time-dependent effects of well point dewatering in multiple layers. The soil profile consists of various homogenous layers with a constant thickness. Both sandy aquifers and less permeable aquitards occur. In sandy aquifers, water flows mainly horizontal. The water flows vertically through moderately permeable aquitards.

Design well-point dewatering

After defining the subsoil model, it is possible to indicate source locations and potential infiltration wells. The number and location of the wells can be adjusted in a simple manner. In addition, it is possible to pinpoint locations for piezometric monitoring of results. This way, the design can be optimized with a minimum of effort.

The figure shows the result of an advice regarding an optimal design of dewatering including infiltration wells near a major construction site. By shifting the location of the infiltration wells and placing them into different aquifers, damage to the surroundings was reduced significantly.

Interpretation aquifer tests

Aquifer tests can be performed in several cases. The results of these tests are used to adjust the subsoil model in such a way that the model fully shows the test results. It is then possible to use this adjusted subsoil model for designing the final dewatering measures and/or adjusting the design.

Monitoring current designs

Monitoring authorities prefer a simple model for the testing of complex designs. With the availability of using MWell, an easy option for preliminary design and review is fit for purpose. The program, that is based on a number of analytical modelling assumptions, allows for fast calculation, systematic design and sensitivity analysis. Despite the schematized modelling, it provides a good insight into time-dependent effects on both groundwater level and settlement.

Settlement

Well-point drainage can have far-reaching consequences for settlements in the area to be drained. MWell provides a first impression of the settlements that can be predicted for the area around a dewatering location.