The SIC software (Simulation of Irrigation Canals) is a mathematical simulation model adapted to most of the world-wide existing irrigation canals. The main purpose of the model is to properly represent the canal hydraulics while at the same time possessing an interface that is as user-friendly as possible.

The model must be able to provide answers to the main problems that confront the canal manager.

In particular, it should be able:

• to simulate the actual hydraulic and operational conditions,

• to test design modifications (hydraulics structures, new calibration, etc.),

• to test new management rules aimed at achieving water savings.

The model has been designed to serve not only as a training and decision-support tool for the canal manager, but also as a research tool for the improvement of the hydraulic functioning of the main canal. The flow simulation in the model is based on one-dimensional hydraulic computations under steady and transient regimes.

The purpose of this note is to present the theoretical concepts on which the model is based, to account for the canal topography, as well as to carry out the hydraulic computation itself.