Attributes:

BILK [-] (node-wise),

BILE [-] (element-wise)

Balance areas are defined in the model file, with the integer value provided in the 1^st to 14^th columns used to identify the balance groups. Decimal places are not taken into account. The element or node numbers are then entered from the 17^th column onwards. Each completed list of numbers forms a balance group.

Balance areas are useful where mass balances are required over certain (potential) boundary sections, watercourses or element leakage areas.

Nodes with fixed potential heads, leakage boundary conditions or seepage boundary conditions can be specified under the BILK data type. When assigned this data type, the mass flow-, leakage- and/or seepage rates of these nodes are listed in the output file and the rates are totalled. Various balance node groups can be specified. Nodes that are not fixed potential heads, leakage boundaries, or seepage boundaries are ignored. The balance areas can be identified via the group number provided in the output file.

Elements with a leakage boundary condition can be specified under the BILE data type. When assigned this data type, the leakage rates of these elements are listed in the output file and the rates are totalled. Several different balance element areas sets can be specified. Elements that are not leakage elements are ignored. The balance element areas can be identified by the group number provided in the output file.