Ground engineering · Groundwater & dewatering

Well pumping: unconfined (Dupuit) & radius of influence calculator

Discharge from a fully penetrating well in an unconfined aquifer with Sichardt's radius of influence.

Standard: Dupuit–Thiem · Sichardt R = 3000 s √k

Inputs in the worked example

The live calculator starts with these values; change any of them and every result, check and diagram updates instantly.

Diagram for the worked example

Water depth in well = 12-5 = 7 m
R = 3000 s √k = 3000*5*SQRT(2.000e-4) = 212.13 m
Q = πk(H² − h²)/ln(R/r) = PI()*2.000e-4*(12^2-7^2)/LN(212.13/0.15) = 0.0082282 m³/s
Q = 0.0082282*1000 = 8.2282 L/s

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For preliminary design and education. Check every result against the current standard and your own engineering judgement before use.