Water Data for Nisqually River Delta at Site D1

An upward-looking acoustic Doppler velocity meter (ADVM, SonTek SW, 3.0 MHz) located in a tidal channel of the Nisqually River Delta at site D1 (N 47d 05’ 37”/W 122d 43’ 17”) measured water level and current velocity at 15-minute intervals from October 14, 2016 to May 31, 2017 (175 days, excluding missing periods). This site is in a tidal channel at a levee breach where flow is tidally influenced. The water depth of the sensor ranged from 0.44 to 4.41 m. The elevation (NAVD88) of the ADVM sensor was survey by RTN-GPS. The offset to convert all water depth time-series data to water surface elevation (NAVD88) is -0.61 m. The water temperature ranged from -0.4 to 22.7 degrees C but may have been bias during periods of low tide due to solar heating of the instrument. Water level in the channel dropped below the elevation of the sensor during periods of low tide. The mean downstream velocity component (Vx) ranged from -0.93 to 0.77 m/s. The mean vertical velocity component (Vy) ranged from -0.14 to 0.14 m/s and mean signal to noise ratio ranged from 12.5 to 45.8 dB. The ADVM measured the water-velocity profile using a dynamic boundary adjustment mode allowing up to 10 velocity measurements in the water-column profile. Time-series gaps of 15-minutes or more are reported as “NA” and occurred when the instrument was offline, when error thresholds were exceeded, or when the water level in the channel dropped below the elevation of the sensor during periods of extreme low tide. Missing periods caused by power failure occurred from November 18-28, 2016; January 6-22, 2017; February 5-17, 2017; and April 1-11, 2017. This site is also referenced as "USGS 12081515 Area One near Olympia, WA". Discrete discharge data at this site are available at: https://waterdata.usgs.gov/wa/nwis/inventory/?site_no=12081515&agency_cd=USGS&;