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Abstract: Measurements of sediment transport (bedload and suspended sediment load) were collected at four sites during a high flow dam release on the Trinity River in May 2011. This spring flow release (nominally 12,000 cfs) was the highest yet made under the auspices of the Trinity River Restoration Program since the Record of Decision in 2000 and provided the opportunity to evaluate sediment transport rates in those areas affected by recent coarse sediment augmentation efforts and in other, less affected, areas. A total of eighty four bedload and forty one suspended sediment samples were collected at the four mainstem sediment transport monitoring stations, Trinity River at Lewiston (TRAL), Trinity River above Grass Valley Creek (TRGV), Trinity River below Limekiln Gulch (TRLG), and Trinity River at Douglas City (TRDC) over the course of the release, spanning from 5/01/11 to 06/07/11. Continuous turbidity records were collected at three of the four sites (none at TRAL due to the very low turbidities which occur such a short distance below the dam) for use as a surrogate for computing continuous suspended sediment concentration. The TRGV site was also operated to collect stage and develop records of continuous streamflow during the release, as this is the one site where a USGS gage is not co-located with the sediment monitoring sites. Thirteen discharge measurements were collected at the TRGV site between April 15 and July 31 (using both conventional and ADCP equipment) and used to develop and shift rating curves for continuous record computation. Computed suspended sediment loads ranged from 2,890 tons at TRAL, to 12,010 tons at TRGV, to 16,000 tons at TRLG, and to 39,800 tons at TRDC. Total computed bedload ranged from 7,170 tons at TRAL, to 3,070 tons at TRGV, to 10,300 tons at TRLG, and to 19,300 tons at TRDC. The percentage of fine and coarse components with total bedload varies considerably by site, as only 10 % percent of the total bedload at TRAL was in the fine (0.5-8mm) size fraction, while TRGV had 26.7%, TRLG had 42.1%, and TRDC 31.7%. The coarse bedload transport was anomalously low at TRGV, compared to the other sites, and especially given that there was considerable injection of gravel by TRRP just a short distance upstream of the sampling section during the peak flow bench.