Groundwater discharge

From Wikipedia, the free encyclopedia

Groundwater discharge is the volumetric flow rate of groundwater through an aquifer.

[edit] Groundwater discharge, Q

Total groundwater discharge, as reported through a specified area, is similarly expressed as:

Q = \frac{dh}{dl}KA

where

Q is the total groundwater discharge ([L³T−1]; m³/s), and
A is the area which the groundwater is flowing through ([L²]; m²)

For example, this can be used to determine the flow rate of water flowing along a plane with known geometry.

[edit] Conservation principle

The conservation principle shows that the mass or volume water flowing into a system is equal to that flowing out, with storage holding or releasing water in the system. Mathematically, this simple concept can be expressed as:

Q_{\mathrm{in}}-Q_{\mathrm{out}}=\frac{\Delta S}{\Delta t}

where

Qin and Qout are the volumetric flow rates in and out the system (such as wells, rivers, etc.),
ΔS is the change of water volume that enters/leaves the system, and
Δt is the change of time

If the system is steady state, then the right-hand side of the equation is 0.

[edit] See also