Download PART Y: IGW Modeling Tutorial

3.3.
ADDING RECHARGE
Recharge can be added to the model in two different ways. First, recharge can be modeled on a zone basis
by accessing the „Sources and Sinks‟ tab of Zone 1001 in the AE. There are three (3) tabs associated with
this subsection (Prescribed Head, Prescribed Flux, and Head-Dependent Flux). Recharge value are entered
under the „Prescribed Flux‟ tab, in the „Recharge‟ field.
This method may present problems if you have more layers in the model (that you will later add as you go
with the tutorial) when trying to model precipitation recharge, due to the possibility of layers becoming dry
(and hence adversely affecting the model solution - a detailed description of this problem is not warranted
in this tutorial though found in the Users Manual).
A more useful method for modeling precipitation recharge is to apply recharge to the first active layer.
This is presented in the following steps. (Note: this process is not layer-specific and therefore does not
depend on which layer is active while performing these steps.)
Step 1:
Select the „Add 3D Attribute Model‟ button. The cursor is now initialized to
add a 3D-attribute feature.
Step 2:
Define a feature that encompasses the entire Working Area (same extent as the parent
zone).
Step 3:
Access this new feature in the AE, under „3D Attributes‟.
Step 4:
In the „Recharge (Apply to first active layer)‟ section, click on „Rech‟, adjust the units
[inch/year], and enter a value [10].
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