Vensim PLE to create models for water management

Abstract

This paper intends to show how easy it can be to build a prototype that will help water resources managers to make their decisions not only based on politics or economics, but also with a scientific tool that will help them build different weather scenarios. First we present a very simple mathematical model that has all the potential to evolve from version to version. Its implementation is easy to do, using a platform to perform simulations, called Vensim PLE. The philosophy that Vensim PLE follows to build up models of simulation is very interesting and simple. It is based in 3 main entities - container variables, auxiliary variables and fluxes. It is a pictorial based language, and therefore, it is quite easy to follow models. The details are hidden when you define these entities represented in a figure. We used a freeware version for students. An example that shows a possible model of what happens in the vicinity of an Urban area is presented, showing it is possible, to use Vensim PLE to build rather complex models of simulation. Provided we have good data, we are able to create different scenarios with literally the click of the mouse in our PC. This paper can help water managers to understand how to implement their own models using a freeware software that is easy to use and produces nice and easy graphs without a lot of effort.