The Maelia project

The Maelia project (Multi-Agent for Environmental Norms Impact Assessment) develops a digital platform for simulating the socio-environmental effects of Global Changes and the implementation of various norms of governance and management of water resources. To address the direct/indirect or expected/unexpected effects of these changes and norms, the platform couples a significant number of stylized dynamics categorized within three major domains: hydrology, agriculture and social. Maelia's contributions are focused on the modeling of low-water management, which is the most strategic issue regarding water resources in the Adour-Garonne basin.

A multiagent platform

The originality of the platform comes from a multiagent approach where a number of software agents simulate the many actors, material and cognitive resources dynamics playing a role in water management.

Maelia is a Java-based simulation platform whose HCI is provided by the Gama framework.


Several technical and conceptual challenges are investigated in Maelia. Managing the data and designing the processes at the heart of the simulation are the most important two.

Data manipulated in Maelia is gigantic and heterogeneous : GIS shapes, databases, PDF documents, spreadsheets, etc. Pre-processing all this data is therefore a mandatory step towards being able to use it. In maelia, every pre-processing routine has been made generic, toroughly documented, and re-usable.

Every change in the simulation is controlled by a process. Processes describe the resources at stake in an interaction between actors and resources, and the dynamics of this interaction. A specific methodology was designed on purpose.


A simulation of Maelia integrates many data sources and many simultaneous dynamics into a consistent whole whose evolution in time can be simulated.