A ship’s channel had been dredged in an area where pipelines crossed a river at three different locations. A comprehensive survey needed to be done to ascertain the cover over each pipeline. The river bottom was imaged using a side scan sonar system. The survey included a dive team, sub-bottom profiling, side-scan sonar and a profiling sonar. The dive team ground truthed some of the sonar findings. In one area a deep scour had exposed the pipe and it was found to be 10’ off the bottom. All data was geo-referenced using an RTK GPS system.