SicWin

The code SicWin (Stocastich IsoChrones) has been developed within the Project W-SAHaRA (Stochastic Analysis of Well-Head Protection and Risk Assessment, supported by the EU within the Fifth Framework, Key Action Water. It simulates pumping of a single well in a uniform base flow and the related spatial distribution of isochrones of an ideal solute. The well is fully penetrating a confined aquifer of given thickness and infinite extent. Aquifer hydraulic conductivity is simulated as a random constant, whose value can be drawn from either a Uniform or a Log-normal probability distribution, chosen by the user.

Input parameters are:
Number of realizations
Target isochrone (days)
Well pumping rate, Q (m^3/s)
Size of the drawing window
Angle of direction uncertainty of the base flow (°)
Minimum and maximum hydraulic conductivity (m/s)

Type of distribution of hydraulic conductivity (Equal or Log-Normal)
Minimum and maximum porosity (-)
Minimum and maximum natural hydraulic gradient (-)
Minimum and maximum aquifer thickness (m)

Simulations of the location of a given isochrone, whose reference time-of-travel is set by the user, are then performed in a Monte Carlo framework.

An example of the spatial distribution of the 50 day isochrones corresponding to 20 Monte Carlo realizations, simulated with the parameters outlined in the previous figure is offered. The demo code is set to perform up to 1500 Monte Carlo simulations and renders contours of percentiles of the (probabilistic) location of the target isochrone.

Percentiles of the 50 days time-of-travel capture zone on the basis of 500 Monte Carlo simulations. Other relevant parameters are specified in the previous slides.

Percentiles of the 50 days time-of-travel capture zone on the basis of 1200 Monte Carlo simulations. Other relevant parameters are specified in the previous slides.

However limited, it gives the user a feeling of the types of answers of a stochastically-based methodology of estimating a time-related capture zone.

Donwload the code (1.5 Mb, compressed)

DISCLAIMER: The authors and the W-SAHaRA Consortium decline any responsibility related to the improper use of this code, outside its scope as a demo. It is the user’s responsibility to verify all the results obtained.