Egis Eau specialises in consultancy and engineering in the fields of water, environment and energy. The firm is active in France and elsewhere in the world for major French and international contracting authorities and for private clients.

Egis Eau grew out of the merging, on 1 July 2011, of the activities of Egis Eau in France and in other countries. Restructuring in this way gave the new Egis Eau an international dimension, allowing the firm to leverage expertise and capacity for innovation recognised in France for many years.