Hydrographic Services

Under-Water Survey

Hydrographic Surveying & Methods:

Hydrographic surveys are completed for channels, rivers, reservoirs, lakes, and ocean bays to create topographic images of underwater surfaces. Hydrographic surveys are performed to map shorelines and bed surfaces beneath a waterway or bodies of water including streams, channels, rivers, reservoirs, lakes, and ocean bays, as well as to establish water depth. Depending on the type of watercourse and the required information, a variety of techniques and watercraft are used including motorized boats, pontoons, rafts, and unmanned RCV’s. Depth soundings are integrated with GPS positions to generate a digital terrain model (DTM) and contours of the bed and shore. Deliverables include DTM surfaces, thalweg profiles (deepest part of the channel), cross-sections, and water volumes. Control Point Associates, Inc. owns and operates several types of equipment specific to hydrographic surveying including boats and high-frequency depth sounders coupled with dual-frequency GPS receivers. Control Point Associates, Inc. has expertise in providing hydrographic survey services for a variety of project types including environmental, transportation, and industrial applications. Projects have been completed for bridge design, outfall scour hole mapping, environmental impact assessments, water intake design, reservoir volumes, and road and canal design.

• Underwater Topographic Surveys
• Surveys extending from the land to water
• Penetration through soft sediment to detect hard bottom elevation
• Check scour around bridges, piers, docks, bulkheads, and seawalls
• Hydrographic Cross Sections
• Mapping for waterfront developers, quarries, reservoirs, rivers, ponds, and lakes
• Pre and Post demolition/construction Hydrographic Surveys