An underwater imaging system is disclosed. A boat sonar transducer is configured to transmit and receive sonar signals and generate an image of water and surfaces using received sonar signals. An active echo system is configured to be positioned within the water to remotely communicate with the boat sonar transducer. The active echo system includes an ultrasound transducer configured to detect sonar signals transmitted by the boat sonar transducer and transmit an active echo pulse, or a series of active echo pulses, back to the boat sonar transducer. A microprocessor is configured to drive the ultrasound transducer to transmit the active echo pulse, or series of active echo pulses, back to the boat sonar transducer in response to the ultrasound transducer detecting sonar signals transmitted by the boat sonar transducer.