Sediment Laboratory Quality Assurance Project Data, 1999 - 2024

The collection and analysis of fluvial sediment samples has been an integral part of hydrologic studies in the United States for over 125 years (Gordon and others, 2000). Accurate measurement of sediment concentrations and its movement in streams is critical to maintaining important infrastructure and habitats in the Nation’s waterways, such as impoundments and estuaries (Hudson and Mossa, 1997; Gellis and others, 2004; Lucena and Lee, 2016). Sediment is also a major pollutant in waterways and represents a concern to all aspects of aquatic ecosystems (Fairchild, 1987), including fate and transport of toxic chemicals (Choi and Chen, 1976).  For several decades, the USGS has made substantial contributions to fulfill this important data need (Gellis and others, 2004).  More than 45,000 suspended-sediment concentration analyses were performed either by or for the U.S. Geological Survey (USGS) between 1999 and 2024.
Scope
This report evaluates laboratory measurements of suspended-sediment concentrations, total sediment mass, grain-size separation, and fine particle-size distributions for performance-testing samples prepared by the USGS Sediment Laboratory Quality Assurance (SLQA) project during 1999 – 2024 (study period). Forty-four different laboratories participated in the SLQA project during the study period (Table 1).   Eleven of those laboratories reported particle-size distribution (PSD) results for SLQA samples during 2005 – 2024.  Results were communicated by the USGS Quality Systems Branch to the participating laboratories within several months of the completion of each study.  Laboratories use the SLQA results to monitor, maintain, and improve performance. There is no intension to rank the participating laboratories or assign laboratory-specific quality ratings to their data.


References

Choi, W.W., and Chen, K.Y., 1976, Associations of chlorinated hydrocarbons with fine particles and humic substances in nearshore superficial sediments: Environmental Science Technology, v. 10, no. 8, pp. 782-786.
 
Fairchild, J.F., 1987, Effects of sediment and contaminated sediments on stream ecosystems: Water, Air, and Soil Pollution, v. 36, pp. 271-293.
 
Gellis, A.C.,  Banks, W.S.L., Langland, M.J., and Martucci, S.K., 2004, Summary of suspended-sediment data for streams draining the Chesapeake Bay Watershed, water years 1952-2002, U.S. Geological Survey  Scientific Investigations Report 2004-5056, 59 p.

Gordon, J.D., Newland, C.A., and Gagliardi, S.T., 2000, Laboratory performance in the sediment laboratory quality-assurance project, 1996 – 98, U.S. Geological Survey Water-Resources Investigations Report 99-4184, 39 p. and appendix.

Hudson, P.F., Mossa, J., 1997, Suspended sediment transport effectiveness of three large, impounded rivers, U.S. Gulf Coastal Plain, Environmental Geology 32 (4), pp. 263-273.

Lucena, Z. and Lee, M.T., 2016, Characterization of streamflow, suspended sediment, and nutrients entering Galveston Bay from the Trinity River, Texas, May 2014–December 2015, U.S. Geological Survey Scientific Investigations Report 2016–5177, 37 p.