Method for controlling the operation of a waste water treatment facility, treatment facility and associated control device

The invention relates to a waste water treatment facility comprising a primary treatment unit (UTP), a biological treatment unit (UTB) and a control unit configured to: * determine a ratio C/N and/or respectively a ratio C/P, between a quantity of organic carbon contained in the water to be treated by the UTB and/or in the water being treated in the UTB, and a quantity of total or partial nitrogen contained in the water to be treated by the UTB and/or in the water being treated in the UTB and/or respectively a quantity of total or partial phosphorus contained in the water to be treated by the UTB and/or in the water being treated in the UTB, * controlling one or more operating parameters of the UTP in order to minimise a difference between the ratio C/N and a first setpoint, and/or respectively in order to minimise a difference between the function C/P and a second setpoint, so as to control, over time, the quantity of organic carbon contained in the water to be treated by the UTB and/or the water being treated in the UTB.