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Tammy

Modflow river sources/sinks values

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I apologize, but I am new to GMS and relatively new to Modflow.  I have a two layer model with glacial till on top of a bedrock layer for a large watershed.  

I have my rivers as a polygon shapefile with the data as attributes. Each cell has one polygon associated with it since I intersected my modflow grid and ID each river segment by the cell number (see image right side:  Top elevation = surface elevation attribute, riverbed elevation= thalwegM_1, and bottom of grid cell is the berktop attribute, and starting head = StartHead1)

I import this into the conceptual model where I have one line for each polygon.  I understand that GMS will multiple my conductance value by the area within each cell.  However, when I map this to modflow, I have multiple lines per grid cell in the River sources and sinks.  Can anyone explain to me where these values are all coming from?  (see image left side)  
I think that they are coming from each effected side of the grid cell?  In this example cell, I don't know where the last line is coming from.  The stage and elevation are much lower and the conductance is so much higher.

Thank you anyone for the clarification! 

Tammy

 

riverSS.jpg

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Based on your picture it looks like you have at least 2 river arcs in each cell so that is where 2 of the 3 river bcs are coming from. The third might be a small intersection from one of the adjacent cell rivers.

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Thanks Alan,

I just can't figure out where the strange values came from.  I imported the rivers as polygons, but maybe I should calculate the area outside of GMS and import the rivers all as arcs.....

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My mistake, from looking at the picture I was thinking that you had 2 river arcs in each cell. I don't think I can diagnose the problem from the description and the pictures here. I recommend contacting support@aquaveo.com so we can take a look at your files see what is going on.

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