Police Cadets will also be involved in the exercise.
Exercise Concordia will take place at several locations along the River Usk and is being coordinated by Dyfed-Powys Police to test policies and procedures in place when dealing with emergency incidents in and around the river.
Sergeant Owen Dillon said: “This exercise has been planned out over the last few months between me and Mark Jones from the Brecon Mountain Rescue Team, working closely with emergency services. The exercise aims to test the response of the emergency services and our voluntary partners to incidents of people requiring emergency assistance at the river.
“This is an opportunity for us to make sure we are in the best position possible, should we be called to emergencies of this nature in the future.
“Residents living in the area will see a large number of emergency service vehicles, staff and students from the Brecon Campus of the NPTC Group as role players taking part in the scenario and are urged not to be alarmed.”