Negative vertical gradient ( z-axis positive downward) corresponding to downward groundwater flow from the Glaciofluvial aquifer to the Saginaw aquifer.  Values range from about 0 to -0.4
 
 
 
 

Positive vertical gradient ( z-axis positive downward) corresponding to upward groundwater flow from the Saginaw aquifer to  the Glaciofluvial aquifer.  Values range from about 0 to +0.4
 
 

Negative vertical gradient ( z-axis positive downward) corresponding to downward groundwater flow from the Glaciofluvial aquifer to the Marshall aquifer.  Values range from about 0 to -0.4
 
 
 

Positive vertical gradient ( z-axis positive downward) corresponding to upward groundwater flow from the Marshall aquifer to  the Glaciofluvial aquifer.  Values range from about 0 to +0.3