The aim of this study was to characterize a chemical release from a submarine breach by quantifying the flow and defining a representation of the dispersion of the chemical leaving the breach. Experimentations carried out consisted in gravity release of chemical in a water column. To achieve this, two different experiments campaign were performed. A small test bench with a double chamber focused on the submerged liquid flow through the orifice. The second experimental apparatus consists of an immerged Plexiglas tank in the large water column (CEC) to study the draining mass flow rate and the fluid flow at the breach level. Silicone oils with different physical properties and di (2-ethylhexyl) adipate were tested to simulate the chemical discharge. Mass flow rate and draining time were measured and a simply model based on Reynolds number power law was proposed to characterize the discharge coefficient. The second experimental phase focuses on the flow behaviour in the water column. Droplet size distribution is evaluated by optical technique and two distributions laws are bring out.