Combined Geotechnical and Geophysical Investigation of Texas Rivers Post Hurricane Harvey.

Hurricane Harvey caused major flooding events across the Gulf of Mexico, leading to geomorphological and site characteristics changes at several rivers. Post hurricane, scour holes and erosion were observed at bridge piers, river embankments, sheet pile walls, boulder walls, and other infrastructure with submerged foundations. To investigate the the local geomorphological changes and sediment dynamics during extreme events, a combination of geotechnical and geophysical methods, that can be deployed from small vessels and shallow waters, were used. The geotechnical methods consisted of a portable free fall penetrometer Bluedrop that penetrates through the riverbed, in addition to a grab sampler to collect disturbed samples. The acoustic methods consisted of a chirp sonar system deployed to resolve the riverbed strata; an acoustic Doppler current profiler (ADCP) Nortek AquaDopp HR to measure the water flow velocity during the survey period; and a side scan sonar to provide riverbed imaging.