Confined - Unconfined Aquifer System

Calculate the radial flow to a well in a confined - unconfined aquifer system.

Solve the governing equation

`1 / r del / (delr) (rbK (delh) / (delr)) = 0 `

where `b =` constant saturated thickness of the aquifer when confined, and `b = h - z_b` when unconfined.
Subject to: `h = h_w` at well radius, `h = h_0` at radius of influence.

Conditions and Assumptions

  1. The aquifer becomes unconfined towards the pumping well
  2. The aquifer is confined at a greater distance from the pumping well
  3. The aquifer has a seemingly infinite areal extent
  4. The aquifer is homogeneous and of uniform thickness over the area influenced by the test
  5. Prior to pumping, the piezometric surface is horizontal (or nearly so) over the area that will be influenced by the test
  6. The aquifer is pumped at a constant discharge rate
  7. The well penetrates the entire aquifer and thus receives water from the entire saturated thickness of the aquifer



 Value of pumping rate for input values:

   Qw =



     Qw =



  Table of Values: Head at radius, r


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