An Environmental Impact Assessment Decision Analysis System for Irrigation Systems

In this paper an Environmental Impact Assessment Multicriteria Decision Analysis System for irrigation
projects (EIAMDAS) used as a comprehensive tool that enables comparison between irrigation
project alternatives is presented. The comparison is based upon all relevant aspects of the surrounding
environment during irrigation systems operation. The decision is case dependent, and relies on the
compromise between positive and negative impacts associated with the project, and the relative importance
(weights) of the different factors involved. Inputs to the EIAMDAS include are information of
the existing system operation derived from selected answers for a set of multiple choice questions that
provide sufficient information to describe the baseline conditions and the general design for several
project alternatives. On the other hand, the EIAMDAS outputs, in the form of positive and negative
scores, allow the user to evaluate different impacts criteria on neighbouring and project areas. The user
is also required to input importance weights to these categories of impacts. The different impacts criteria
are categorised as environmental social and economic impacts using compromise programming.
The final output is an overall environmental index for each project alternative. Two years of real time
control data are used to illustrate system performance. Conclusively the EIAMDAS is an efficient tool
for supporting the decision making process, especially in the trade-off between project alternatives
according to anticipated environmental impacts including economic aspects. Although this EIAMDAS
was developed for irrigation projects applications, the software was designed in a flexible manner to
allow for future adaptation to other applications using the same technique.