One consequence of increasing urban development is ever larger volumes of effluent being released from wastewater treatment plants. Energy production, industry and desalination also use water in different processes. Outfalls must be designed to ensure that effluent is dispersed and diluted without any risk of harmful effects on water quality and the environment. Water intakes must also be carefully positioned to avoid any risk of recirculation, which can have an adverse effect on the efficiency of the installations. Artelia has carried out numerous studies of river and sea outfalls, and possesses tried and tested modelling tools (2D and 3D models in the case of heated water and saline discharges) and solid experience in designing and locating such structures. It also supervises outfall construction works.