Theis Drawdown Calculator
Compute Theis non-equilibrium drawdown in meters from discharge (m3/day), transmissivity (m2/day), radial distance (m), storativity and elapsed time (days).
Description
Compute Theis non-equilibrium drawdown in meters from discharge (m3/day), transmissivity (m2/day), radial distance (m), storativity and elapsed time (days).
Theis Drawdown Calculator: Compute Theis non-equilibrium drawdown in meters from discharge (m3/day), transmissivity (m2/day), radial distance (m), storativity and elapsed time (days).
When to use Theis Drawdown
Use this geological calculation for a transparent first-pass interpretation of measured rock, soil, fluid, well, stratigraphic, isotopic, geophysical, or seismic data under an explicitly selected model.
- Q
- Constant pumping discharge in cubic meters per day.
- T
- Transmissivity in square meters per day.
- r
- Radial distance from the well in meters.
- S
- Aquifer storativity (dimensionless).
- t
- Time since pumping began in days.
How Theis Drawdown works
Compute Theis non-equilibrium drawdown in meters from discharge (m3/day), transmissivity (m2/day), radial distance (m), storativity and elapsed time (days). The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.1
- u
- Dimensionless argument u = r^2 S / (4 T t).
- W(u)
- Theis well function W(u).
- s
- Drawdown at the observation point in meters.
Limitations and assumptions
- Aquifer calculations assume a geometry, boundary condition, flow regime, hydraulic properties, well construction, and observation response. Heterogeneity, anisotropy, leakage, storage, partial penetration, recharge, and pumping history can invalidate simple analytical solutions.
- Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.
Alternative or Complementary approaches
Compare independent measurements and models, retain units and analytical metadata, propagate uncertainty, and validate interpretations against logs, cores, maps, laboratory data, or field observations.
References
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Hydrogeology — Wikipedia contributors
Similar or alternative tools
- Jacob Drawdown Calculator
Compute the Cooper-Jacob straight-line approximation of drawdown in meters from discharge (m3/day), transmissivity (m2/day), radial distance (m), storativity and time (days).
- Cooper Jacob Transmissivity Calculator
Compute aquifer transmissivity in square meters per day from constant discharge in cubic meters per day and the semilog drawdown change per log cycle of time in meters.
- Recovery Residual Drawdown Calculator
Compute Theis recovery residual drawdown in meters as Q / (4 pi T) times the natural log of pumping duration over time since recovery began (days).