Dear WEAP Forum users,

I have a question about modeling groundwater-surface water interactions in WEAP. According to the WEAP Help documentation ( https://www.weap21.org/WebHelp/Using_the_Purkey_Wedge_Method.htm ), there are four methods for modeling GW-SW interactions.

My question is, if I define the method as "Model GW-SW flows" under the groundwater tab, where can I define how it is modeled? Does it use the wedge method by default, or do I need to choose one of the following methods?

2. Have WEAP model these interactions (groundwater "wedge" connected to river)
3. Have WEAP model these interactions (deep soil layer of Soil Moisture method catchment)

I am modeling agricultural areas in MABIA and urban areas in the soil moisture method. Based on previous WEAP forum posts, I understand that the soil moisture model defines the bottom bucket as the groundwater node if it is connected to a groundwater node. Otherwise, it directs the deep percolation as baseflow to the river. However, for the MABIA method, the catchment must be connected to a groundwater node to model GW-SW interactions.

Thank you in advance.

Esin

Dear Esin,

Choosing "Model GW-SW" only uses the wedge model, and only works with groundwater nodes, not the second bucket in the Soil Moisture method.

Anne