Suspended-sediment transport is a critical element governing the geomorphology of tidal marshes. Marshes rely both on organic material and inorganic sediment deposition to maintain their elevation relative to sea-level. In wetlands near the Blackwater National Wildlife Refuge, MD, portions of the salt marsh have been subsiding relative to sea level since the early 20th century. Other portions of the marsh have been successful at maintaining elevation. The USGS undertook measurements of suspended-sediment concentration in the tidal channels in order to understand the magnitude of suspended-sediment concentrations, the sediment-transport mechanisms, and relative differences between the two areas of the marsh. We deployed optical turbidity sensors and acoustic velocity meters at multiple sites over two periods in 2011. The time-series of oceanographic data collected during those field studies, including velocity, depth, turbidity, salinity, water temperature, and pH are presented here. For more information on the field operations associated with data collection: https://cmgds.marine.usgs.gov/fan_info.php?fan=2011-017-FA; https://cmgds.marine.usgs.gov/fan_info.php?fan=2011-029-FA; https://cmgds.marine.usgs.gov/fan_info.php?fan=2011-044-FA; https://cmgds.marine.usgs.gov/fan_info.php?fan=2011-050-FA;