Dredging apparatus for removing sediments from a bed of an expanse of water in absence of any contact with the bed, comprising a suction apparatus including: a) a submersible pump including: a1) a housing body provided with an inlet mouth and with a discharge opening; a2) an impeller rotatably supported in said body between said inlet mouth and said discharge opening and rotatably driven by a respective driving device; b) a suction head associated to said inlet mouth of the housing body of the pump and provided at the bottom with a suction opening of the sediments; wherein the suction opening of the head has a value of the cross-section area dimensioned to achieve in the working range of the pump a suction speed capable of removing the sediments by means of the fluid dynamics removal action carried out by the water sucked into said head; characterised in that the dredging apparatus further comprises a separating device for separating a slurry of water and sediments discharged from the suction apparatus in a liquid phase and a solid phase including the sediments and a recirculation system to the suction head of at least a part of the liquid phase separated by said separating device, in that the suction opening of the head has a cross-section area smaller than the maximum cross-section area of the suction head, in that said suction head is provided with an inner hollow space defining an outer annular portion of said suction opening and in liquid communication with the recirculation system for feeding the liquid phase separated by the separating device towards the suction opening and inside said head, and in that the recirculation system defines a closed hydraulic circuit of the fluid recirculating therein. a) a submersible pump including: a1) a housing body provided with an inlet mouth and with a discharge opening; a2) an impeller rotatably supported in said body between said inlet mouth and said discharge opening and rotatably driven by a respective driving device; a1) a housing body provided with an inlet mouth and with a discharge opening; a2) an impeller rotatably supported in said body between said inlet mouth and said discharge opening and rotatably driven by a respective driving device; b) a suction head associated to said inlet mouth of the housing body of the pump and provided at the bottom with a suction opening of the sediments; wherein the suction opening of the head has a value of the cross-section area dimensioned to achieve in the working range of the pump a suction speed capable of removing the sediments by means of the fluid dynamics removal action carried out by the water sucked into said head; characterised in that the dredging apparatus further comprises a separating device for separating a slurry of water and sediments discharged from the suction apparatus in a liquid phase and a solid phase including the sediments and a recirculation system to the suction head of at least a part of the liquid phase separated by said separating device, in that the suction opening of the head has a cross-section area smaller than the maximum cross-section area of the suction head, in that said suction head is provided with an inner hollow space defining an outer annular portion of said suction opening and in liquid communication with the recirculation system for feeding the liquid phase separated by the separating device towards the suction opening and inside said head, and in that the recirculation system defines a closed hydraulic circuit of the fluid recirculating therein.