How Many Gallons per Minute do I Need to be Pumping for that Pivot?

How Many Gallons per Minute do I Need to be Pumping for that Pivot?

How Many Gallons per Minute do I Need to be Pumping for that Pivot?

When replacing water in your profile via irrigation, it is important to know who much you need to use in order to reach your intended application. The following formula can help with that.

How many gallons per minute do I need to be pumping for that pivot?                            
    Qpump  =  [ 18.9 x ETp x Area ] / [ Ea x Tirr ]                        
    where,                        
    Qpump   = gross pumping rate, gallons per minute                        
    K           =  18.9 = conversion constant                        
    ETp       =  peak water use rate, inches per day                        
    Area      =  irrigated area, acres                        
    Ea         =  application efficiency, decimal                        
    Tirr        =  portion of day the system is operating, decimal                        

    K    18.90    Constant                
    Peak daily water use    0.25    Inches per day                
    Irrigated area    110    Acres                
    Application Efficiency    90%    Percentage                
    Percentage of the day that the system runs    90%    Percentage                

    Gross Pump capacity Needed    642    Gallons per minute

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