u.s. department of the interior u.s. geological survey shallow water hydrographic surveying using a...
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U.S. Department of the InteriorU.S. Geological Survey
Shallow Water Hydrographic Surveying using a High Resolution Multibeam Echosounder
Richard C. Wilson, P.E., andBrenda K. WoodwardNebraska Water Science Center
2010 Tri-Agency MeetingOct. 5, 2010
Hydrographic Surveying• Aristotle observed that sound could
be heard in water• Allies invent the sonar during
World War I• Coast and Geodetic Survey deployed
the Fathometer in 1925 • U.S. Navy deployed a multibeam
echosounder in the 1960s
Hydrographic Surveying - Purposes
• Navigational aide• Quantity surveys• Inspections of dams, bridges, and water control structures• Habitat assessments• Hydrodynamic and sediment-transport models• Geomorphic assessments
Single-Beam Echosounder
Multibeam Hydrographic Surveying
• Wide yet narrow swath perpendicular to the boat direction• Multiple beams in just one ping• SURVEYS the ENTIRE RIVER or LAKE BED
Shallow Water Multibeam Hydrographic Surveying•Minimum depth is 1 meter•Swath angle 128° or width-to-depth ratio 3.5 to 1 •Rotation of the transducer for surveying horizontal features•Use Single and Multibeam Echosounders, together•Flat keel boat•Obstructions
Multibeam Echosounder
RESON Seabat 7125 Multibeam Echosounder System
•Digital beam-former •400 kHz•256 or 512 beams•128° swath angle•200 meter range•Bathymetry data and Side-Scan imagery
Multibeam Echosounder Components
ProjectorArray
ReceiverArray
SoundVelocityProbe
Multibeam Echosounder Components Real-Time Kinematic Global Positioning System (RTKGPS) or Differential Global Positioning System (DGPS)
InertialMeasurementUnit (IMU) Navigation computer
Position and OrientationSolution (POS-MV) motion control unit
7-P sonar signal processor
Sonar display
Patch Test CalibrationRoll correction
Pitch correction
Yaw correction
Nadar Beam
Collapsed Historical Bridge Deck near Warsaw, Missouri
Bridge Piers near Warsaw, Missouri
Bridge Pier near Warsaw, Missouri
Multibeam Data Processing
•Dell Precision T7500•Intel Xeon Quad Core Processor 3.46 GHz•12GB DDR3 SDRAM, 1333MHz, •2 GeForce GTX 480 2.0 Graphics Card
Multibeam Data Processing
Line-by-line swath editing is necessary
Multibeam Data Processing
Gavins Point Dam Multibeam SurveyPurpose:
•Document change from 1957-2008
•Verify the integrity of energy dissipation structures
•Create updated bathymetric contours
Gavins Point Dam Spillway
Energy Dissipation Structures
•Determined the structural integrity
•Divers were not needed, eliminating a safety hazard
•Measured change to 0.1 M
Gavins Point Dam - Spillway Intake
Missouri River BendsMissouri River Habitat Assessment and Monitoring Program (HAMP)
• Habitat improvement through structure modification• Wing dike notches• Chevrons• Parallel dikes• Revetment removal
Hydrographic Surveys of Glovers Bend
•Single-beam echosounder•Glovers Bend, Missouri River•2007
Hydrographic Surveys of Glovers Bend
•Multibeam echosounder•Glovers Bend, Missouri River•2009
Hydrodynamic Modeling of the Missouri River using MD_SWMS
Experimental Advanced Airborne Research LiDAR (EAARL)
Water penetrating LiDAR
Uses Blue-green laser
NASA/USGS Technology
Shallow water EAARL survey, Central Platte River
Side-Scan Sonar: Using Backscatter Intensity to Classify Substrate
Robert B. SwansonDirector(402) [email protected]
Richard C. Wilson, P.E.Associate Director of Hydrologic Studies (402) [email protected]
Ronald B. ZeltAssociate Director of NAWQA Studies(402) [email protected]
Jason M. LambrechtAssociate Director of Hydrologic Data(402) [email protected]
CONTACT INFORMATION: Rick Wilson USGS Nebraska Water Science Center (402) 328-41205231 South 19th St. [email protected], NE 68512-1271 http://ne.water.usgs.gov