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Hurricane Harvey, a category 4 hurricane on the Saffir-Simpson hurricane wind scale that approached from the Gulf of Mexico, caused severe flooding in Texas and Louisiana. Recorded water levels along the Brazos River exceeded historic high-water levels, and erosion and slope failures of riverbanks were observed in many locations along the river. A near-surface site investigation was conducted in the Brazos River along a short section in Sugarland, Texas, post-Hurricane Harvey. In situ tests were conducted using a portable free fall penetrometer and a chirp sonar. Results showed that sediment properties varied between different locations. Weaker sediments underlying a loose top layer were observed at both riverbanks reaching a penetration depth of ~20 cm, whereas stiffer sediments were found at the center of the river with an estimate of maximum quasi-static bearing capacity ranging from 25 to 300 kPa at sediment depths less than 7 cm. Particle size distributions varied as well depending on the location. Results suggest a correlation between sediment strength and backscatter intensity of the chirp sonar. In summary, in situ geotechnical properties across and along short sections of the Brazos River exhibited a significant variability, likely governed by the local sediment remobilization processes that was reflected in portable free fall penetrometer and chirp sonar measurements of the riverbed surface.