In Reply Refer To:                                         December 16, 2003 
Mail Stop 415

OFFICE OF SURFACE WATER TECHNICAL MEMORANDUM NO. 2004.01

Subject: Water Resources Discipline Policy on Storage and Publication of Fluvial-Sediment Data with Updated Method Codes

BACKGROUND

Methods for producing data describing selected properties of fluvial sediment have evolved since 1993 when Office of Surface Water (OSW) Technical Memorandum 93.11, "Water Resources Division Policy on Publication of Sediment Size Data Determined by use of the Sedigraph," was released. The purpose of this memorandum is to provide an updated list of method codes associated with selected fluvial-sediment parameter codes to enable storage and, as appropriate, publication of sediment data produced by these methods. The method codes and related information herein supplement the contents of OSW Technical Memorandum 93.11.

The Water Resources Discipline (WRD) has traditionally published suspended-sediment concentration data produced by the evaporation, filtration, or wet-sieving-filtration methods as described by ASTM Designation D 3977-97, "Standard Test Methods for Determining Sediment Concentration in Water Samples" (ASTM International, 2000). Published suspended particle-size distribution data have been produced based on the fall diameter property of sediment using the visual-accumulation tube, pipet, bottom withdrawal tube, hydrometer, and Sedigraph. Published bedload and bed-material data have been produced by dry-sieve (and in some cases wet-sieve) methods (Knott and others, 1992, 1993; Matthes and others, 1991).

Use of technologically advanced field- and laboratory-based methods that infer selected properties of fluvial sediment based on one of the following properties – bulk optics (attenuation and scatterance), acoustic backscatter (single and multi-frequency), laser diffraction, digital photo-optic imaging, and pressure difference (Gartner and Gray, 2003) is becoming relatively commonplace. Some of these advanced methods—particularly those based on bulk-optic principles—are increasingly being tested and in some cases deployed to obtain discrete surrogate data, or a continuous surrogate time series for selected characteristics of fluvial sediment. To be of maximum use, these data must be quality assured and stored in the National Water Information System (NWIS) databases (ADAPS and QWDATA). However, the potential for confusion on the part of data users regarding the method by which selected fluvial-sediment data were obtained necessitates pairing appropriate method codes with appropriate parameter codes in the NWIS databases. To this end, new method codes have been developed to supplement those described in OSW Technical Memorandum 93.11.

POLICY

All fluvial-sediment data entries to NWIS databases are to include a method code from the following table:

 
Method Code
Method Code Description
ADAPS DD Description
Used for Type(s) of Analyses
Associated Family of Particle-Size Parameter Codes
A
measurement by filtration
meas, filtration A
concentration only
 
E
measurement by evaporation
meas, evaporation E
concentration only
 
Q1,2
measurement by pressure difference
meas, pressure difference Q
concentration only
 
C2
measurement, manual, particle count
meas, manual, particle count C
particle size only
direct measurement
H2
hydrometer
hydrometer H
concentration and particle size
fall diameter
V
visual accumulation tube
VA tube V

concentration and particle size

fall diameter

S
Sedigraph
sedigraph S

concentration and particle size

fall diameter

P
pipette
pipette P

concentration and particle size

fall diameter

M1,2
Measurement by photo optics
meas, photo optic M

concentration and particle size

direct measurement

L1,2
measurement by laser
meas, laser L

concentration and particle size

direct measurement

D
dry sieve
dry sieve D

concentration and particle size

sieve diameter

B
bottom withdrawal
bottom withdrawal B

concentration and particle size

fall diameter

W
wet sieve
wet sieve W

concentration and particle size

sieve diameter

Z1,2
measurement by acoustic backscatter
meas, acoustic backscatter Z
concentration and particle size
direct measurement
T1,2
surrogate, regression analysis by turbidity3
regression, turbidity T
concentration and sediment discharge
 

1 These method codes are currently unsupported by approved protocols. 

2 Method codes associated with field-determined values must be entered into the NWIS database by the data collector or provider.

3 Turbidity is being measured with different technologies, including turbidimeters, optical backscatter meters, and optical transmissometers (U.S. Geological Survey Circular 1250, pp. 41-43); the next update of U.S. Geological Survey Techniques of Water-Resources Investigations Book 9, Chapter 6.7 will contain additional information on this subject (Gray and Glysson, 2003; U.S. Geological Survey, 2003a).


 
For samples analyzed by WRD sediment laboratories, the Sediment Laboratory Environmental Data System (SLEDS) software 
(USGS, 2003b) will soon be providing Districts with NWIS-compatible data files that will include all of the sediment-size 
classification parameters and associated method codes.  Method codes related to field determinations or for analyses 
performed locally in the absence of the SLEDS software must be entered into the database by the data collector or provider.  
Method codes for historical data may be entered at the discretion of the individual District. 

All data stored in publicly accessible U.S. Geological Survey databases (NWISWeb and other publicly accessible files) 
must be collected and analyzed using approved collection and analytical protocols.  The following new method codes are 
not fully supported by published protocols at this time:  Q (measurement by pressure difference), M (measurement, 
photo optics), and L (measurement by laser), Z (measurement by acoustic backscatter), and T (surrogate, regression 
analysis by turbidity).  Data collected or analyzed by unapproved protocols, including those listed above, must be 
flagged in the QWDATA and ADAPS databases so that they are not made available to the public.  To this end: 

QWDATA:  Sediment data collected or analyzed by unapproved methods and stored in QWDATA should be assigned an appropriate data quality indicator code.  A code of "U" indicates an unapproved collection or analysis method.  A description of available data-quality indicator codes can be found in Appendix A, table 14 of the NWIS QWDATA documentation (http://wwwnwis.er.usgs.gov/nwisdocs4_3/qw/QW.user.book.html).   

ADAPS: Time series sediment data collected or analyzed by unapproved methods and stored in ADAPS must be qualified by the following procedures: 

1.  The data should be stored in a data descriptor that is not marked primary. 
2.  The optional 'DD Description' text field should be used to store the ADAPS DD Description precisely 
    as shown in the third column in the table above. 
3.  The data should be left in the 'working' data-aging status, or if it is necessary protect against changes, 
    in the 'in-review' data-aging status. The data should not be marked 'approved'. 

These data-storage procedures should ensure that data collected or analyzed using unapproved methods are not 
released to the public, while allowing for both storage of the data and their subsequent approval if and when 
a given method is approved. 


        /signed/ 

Stephen F. Blanchard 
Chief, Office of Surface Water 


This memorandum supplements OSW Technical Memorandum 93.11. 

Distribution Code:  A, B, FO, PO, DC, and CD 


REFERENCES CITED: 
        
ASTM International, 2000, Standard Test Method for Determining Sediment Concentration in Water Samples: 
D 3977-97, Vol. 11.02, Water (II), pp. 395-400. 

Gartner, J.W., and Gray, J.R., 2003, Summary of suspended-sediment technologies considered at the interagency 
workshop on turbidity and other sediment surrogates:  Federal Interagency Workshop on Sediment Monitoring 
Instrument and Analysis Research, Sept. 9-11, 2003, Flagstaff, Arizona, 9 p., available at 
URL: http://water.usgs.gov/osw/techniques/sediment/sedsurrogate2003workshop/gartner_gray.pdf. 

Gray, J.R. and Glysson, G.D., 2003, Proceedings of the Federal Interagency workshop on turbidity and other 
sediment surrogates, April 30-May 2, 2002, Reno, Nevada:  U.S. Geological Survey Circular 1250, 56 p. plus 
appendix 2, which is available only on-line:  Accessed November 24, 2003 at: 
http://pubs.usgs.gov/circ/2003/circ1250/ . 

Knott, J.M., Sholar, C.J., and Matthes, W.J., 1992, Quality Assurance Guidelines for the Analysis of 
Sediment Concentration by U.S. Geological Survey Sediment Laboratories: U.S. Geological Survey Open-File 
Report 92-33, 30 p. 

Knott, J.M., Glysson, G.D., Malo, B.A., and Schroder, L.J., 1993, Quality Assurance Plan for the Collection 
and Processing of Sediment Data by the U.S. Geological Survey, Water Resources Division: U.S. Geological 
Survey Open-File Report 92-499, 18 p. 

Matthes, W.J., Jr., Sholar, C.J., and George, J.R., 1991, A Quality-Assurance Plan for the Analysis of 
Fluvial Sediment by Laboratories of the U.S. Geological Survey:  U.S. Geological Survey Open-File Report 
91-467, 31 p. 

U.S. Geological Survey, 2003a, Turbidity, in, National Field Manual:  Techniques of Water-Resources 
Investigations Book 9, Chapter 6.7:  Accessed November 24, 2003, at 
http://water.usgs.gov/owq/FieldManual/Chapter6/6.7_contents.html. 

U.S. Geological Survey, 2003b, Cascades Volcano Observatory Sediment Laboratory Environmental Data 
System Program:  Accessed September 26, 2003 at http://eris.wr.usgs.gov/SedLab/framework.html.