Long Engineering, Inc. is now utilizing echo sounding technology for our hydrographic surveys. Echo sounding is a type of sonar used to determine the depth of water by transmitting sound pulses into water. The time interval between emission and return of a pulse is recorded, which is then used to determine the depth of water. The horizontal locations of the soundings are determined by connecting our GPS units to the echo sounding equipment. Combining these two technologies has allowed us to provide precise and accurate topography survey of rivers, channels, and lake bottoms that are not achievable with traditional surveying equipment. Long Engineering, Inc. has utilized echo sounding technology for surveys of the Savannah River, Lake Jackson, and the Middle Oconee River.