Provided are a sonar system and transducer assembly for producing a 3D image of an underwater environment. The sonar system may include a housing mountable to a watercraft having at least one transducer array. The transducer array may include a transmit/receive element configured to transmit sonar pulses and a second transducer element. The transmit/receive element and the second transducer element may receive first and second sonar returns convert the first and second returns into first and second sonar return data. A sonar signal processor may then generate a 3D mesh data using the first and second sonar return data and at least a predetermined distance between the transducer elements. An associated method of using the sonar system is also provided.