A multibeam hydrographic survey was conducted on a 46 km² reservoir in Malaysia in 2011. Updated reservoir volume and surface area elevation curves were required being critical tools for the management of the dam. A review of current single beam and multibeam sonar survey technologies is detailed as well as the decision process that led to the survey method selection for the assignment. The survey including planning, methodology, data collection and post processing is discussed as well as the quality assurance and quality control program implemented. Finally, the outputs are described and the question whether the survey technique improves value and productivity is addressed.