Hydrography surveying
Jasper Schaer, Hydro Survey Team, retrieves a GPS sounding tool during a post dredge survey as James Hiroms, boat captain observes. Schaer and Hiroms both work for the U.S. Army Corps of Engineers Galveston District. Calibrating sonar instruments to local water quality is an important part of taking accurate measurements during a survey. Sounding measures the speed at which the single beam sonar waves pass through the water. When a large ship passes, it disturbs sediment which slows down the sonar signal. Frequent sounding checks ensure precise measurement of the dredge material removed.

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Photo by: Luke Waack |  VIRIN: 230605-A-XJ740-0048.JPG

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