Leakage coefficients

When the groundwater leakage boundary condition is included, the coefficients (global and local coefficients) controlling the rate of the leakage must be specified in the 'Leakage coefficients' editor.

Leakage coefficients may be defined by a default (global) leakage coefficient or by local coefficients that override the default value at specific locations. Hence, if leakage is to be included only at some locations, then a default value of 0 must be defined and the local reaches where groundwater leakage takes place must be defined in the Local coefficients table.

The Leakage coefficients' editor will appear in the Setup tree view, when a 'Groundwater leakage' boundary condition exists.

Default coefficient

A default leakage coefficient is defined at the top of the editor. It is applied throughout the channels network unless local values have been defined.

Local coefficients

By using local leakage coefficients, it is possible to adjust the flow towards the groundwater, to reflect local variations of soil characteristics within the domain. Local values overwrite the default value. Local values are applied at specific locations defined by the channel ID and a chainage value.

Local values are added or deleted using the 'Insert' or 'Delete' buttons above the table.

Note

If two or more local values are defined in the same river, the intermediate value(s) will be calculated by linear interpolation.