John R. Gray^1^and G. Douglas Glysson^2^

^1^ U.S. Geological Survey, 415 National Center, Reston, VA 20192

^2^ U.S. Geological Survey, 412 National Center, Reston, VA 20192

**Keywords**: fluvial sediment, monitoring and research,
sediment-surrogate technology

###### ABSTRACT

The number of daily fluvial-sediment data-collection stations operated
by the U.S. Geological Survey has declined by almost two-thirds since
1980. This decline has occurred concomitant with a substantial increase
in sediment-data needs, and increased availability of potentially useful
sediment-surrogate monitoring technologies that lack Federal sanction. A
Sediment Monitoring Instrument and Analysis Research Program is
envisioned for the United States that would foster research, testing,
and evaluations on instruments and methods for measuring, monitoring,
and analyzing selected characteristics of fluvial sediments by
cost-effective, safe, and quantifiably accurate means. The Federal
Interagency Sedimentation Project represents a potential focal point for
management of a Sediment Monitoring Instrument and Analysis Research
Program.

###### INTRODUCTION

According to the U.S. Environmental Protection Agency (2002),
siltation---also referred to as sedimentation---remains one of the most
widespread pollutants affecting assessed rivers and streams. In
additional to traditional uses of sediment data, such as for design and
management of reservoirs and hydraulic structures, information is needed
for contaminated sediment management, dam decommissioning and removal,
environmental quality, stream restoration, geomorphic classification and
assessments, physical-biotic interactions, the global carbon budget, and
regulatory requirements of the 1972 Clean Water Act, including the U.S.
Environmental Protection Agency's Total Maximum Daily Load Program (U.S.
Environmental Protection Agency 2003). The need for reliable,
cost-effective, spatially and temporally consistent data to quantify the
clarity and sediment content of waters of the United States (U.S.)
arguably has never been greater.

In spite of the need for more sediment data, there is evidence that the
amount of nationally consistent daily sediment data being collected in
the U.S. today is but a third of that collected in 1982. This is due in
part to cost, accuracy, and safety issues (Gray 2002, Gray et al. 2002).

Although traditional methodologies that normally require collection and
analysis of a physical water sample are well established, these methods
are increasingly being forsaken in favor of less expensive, potentially
safer, continuously recording in-situ or laboratory methods for
monitoring water clarity and (or) for obtaining sediment-surrogate data.
Turbidity and related bulk-optic measurements are the most common means
for obtaining water-clarity data, and for inferring suspended-sediment
concentrations. Other sediment surrogate techniques, including those
based on laser-optic, digital-optic, acoustic, and pressure-differential
technologies, also are being deployed and (or) tested in field and
laboratory settings for their applicability toward providing
quantifiably reliable information on bedform and bed-material
characteristics, and on concentrations, size-distributions and transport
rates of suspended sediment and (or) bedload. However, there are no
nationally accepted standards for collection, storage, or use of data
derived from techniques other than those described by Edwards and
Glysson (1999). Additionally, there is a perceived need for a better
understanding and standardization of data produced by these
technologies.

That perceived need was part of the impetus for holding the Federal
Interagency Workshop on Turbidity and Other Sediment Surrogates, April
30-May 2, 2002 (U.S. Geological Survey 2002, Gray and Glysson 2003). The
workshop breakout session that focused on suspended-sediment-surrogate
technologies other than those based on bulk-optic properties of water
proposed four recommendations to the workshop's sponsor, the Federal
Interagency Subcommittee on Sedimentation (Glysson and Gray 1997). The
recommendations are summarized as follows:

The fluvial-sediment data needs of the U.S. would be well served by:

(1) Forming a program to foster research, testing, and evaluation of
    instruments and methods for measuring, monitoring, and analyzing
    selected characteristics of fluvial sediments in cost-effective,
    safe, and quantifiably accurate means.

(2) Establishing and fostering group(s) of topical expert advisors,
    composed of private, Federal, State, and (or) academia, to advise
    the Subcommittee on Sedimentation.

(3) Enhancing communication among those producing or using
    sediment-surrogate instruments or data.

(4) Establishing and promulgating criteria for suspended-sediment data
    accuracy.

This paper addresses the first recommendation by proposing attributes of
a Sediment Monitoring Instrument and Analysis Research Program (SMIARP).
Activities under a SMIARP would include research on bedload, bed
material, bedforms, and water clarity in addition to suspended sediment.
Several of the suggested SMIARP attributes have already been considered
by the Technical Committee of the Federal Interagency Subcommittee on
Sedimentation for incorporation into the activities of the Federal
Interagency Sedimentation Project (2003).

###### A SEDIMENT MONITORING INSTRUMENT AND ANALYSIS RESEARCH PROGRAM

A SMIARP would focus on instruments and methods for providing
quantifiably reliable information on bed-material characteristics, and
on concentrations, size distributions and transport rates of sediments
in suspension and as bedload by the safest, most cost-effective, and
quantifiably accurate means. In this section, a vision of a SMIARP is
framed as if currently functional.

Goal: The goal of the SMIARP is to foster research, testing, and
evaluations on instruments and methods for measuring, monitoring,
analyzing (including computing, and estimating) selected characteristics
of fluvial sediments in cost-effective, safe, and quantifiably accurate
means. The methods and standards developed through the SMIARP must
ultimately be acceptable to the Federal Interagency Subcommittee on
Sedimentation. It is also desirable that these methods and standards
ultimately be deemed acceptable by such standards-setting organizations
such as ASTM International (2003) and the International Standards
Organization (2003).

Scope: The technical scope of the SMIARP includes research on or related
to instruments and methods for remote, in-situ, manual and (or)
laboratory measurement of selected characteristics of suspended sediment
and water clarity, bedload, bed material, and bedforms. The scope
includes research on computational and estimating techniques; the most
efficient linkage or usage of instruments, methods, and data-analysis
techniques; and efficient storage and public retrieval of the types and
amounts of sediment and ancillary data needed by the U.S.

Functions: The primary functions of the SMIARP are to recommend and (or)
provide a formal structure and organization for collaboration; standard
data-collection and test protocols; and standard acceptance criteria.
The SMIARP also represents a forum or clearinghouse for effective
communication among public and private entities; and, in some cases, a
source of support for organized collaboration on fluvial-sediment
research that has a high potential to result in operationally effective
tools for providing the sediment data needed by the U.S.

**Activities**: The concept of the SMIARP is evolving and the full range
of Program's potential endeavors are being considered. The following
list represents appropriate activities that may be conducted under the
auspices of the SMIARP (numbering the activities is for ease in
reference and does not imply priority):

1.  Develop and publish criteria describing the acceptable
    documentation, qualification, and reporting of data describing
    selected characteristics of suspended sediment, bedload, bed
    material, and bed topography in field and laboratory settings
    acceptable by standards-setting organizations.

2.  Develop and publish quantifiably reliable procedure(s) for testing
    the precision and bias associated with data obtained by surrogate
    measurements.

3.  Identify instruments, methods, and analytical techniques that show
    considerable promise for providing surrogate data for fluvial
    sediment in laboratory and field settings.

4.  Test sediment-surrogate instruments in laboratory and (or) in field
    settings, with the primary goal to describe the capabilities and
    limits; bias and variance; and requisite ancillary data associated
    with the instruments.

5.  Develop and (or) test analytical techniques for computing or
    estimating selected characteristics of fluvial sediment, including
    transport rates, size distributions, and their associated
    uncertainties.

6.  Prepare and disseminate reports that summarize program findings and
    results.

7.  Organize and hold joint briefings, workshops, national meetings, and
    (or) otherwise encourage effective communication with program
    collaborators, the Subcommittee on Sedimentation, its Technical
    Committee, and the Federal Interagency Sedimentation Project.

8.  Fund projects, or assist in obtaining project funds to accomplish
    specific program objectives for which existing resources are
    inadequate.

9.  Evaluate the effectiveness of the SMIARP and refine its mission and
    (or) functions to optimize its responsiveness to participants.

**Leadership and Participation**: One of the explicit reasons for
holding the Federal Interagency Workshop on Turbidity and Other Sediment
Surrogates---and one of its implicit outcomes---was recognition of the
need for Federal leadership in setting standards and providing guidance
for measurement of fluvial sediment and water clarity. The Federal
Interagency Sedimentation Project (FISP) was created in 1939 to unify
the research and development activities of Federal agencies involved in
fluvial-sediment studies. Today, oversight for the FISP is provided by
the Federal Interagency Subcommittee on Sedimentation, Technical
Committee, which is comprised of the U.S. Environmental Protection
Agency; U.S. Army Corps of Engineers; U.S. Department of Agriculture's
Agricultural Research Service, and Forest Service; and the Department of
the Interior's Bureau of Land Management, Bureau of Reclamation, and
U.S. Geological Survey. FISP equipment and techniques are the standards
used by most Federal, State, and local governments, and private
organizations collecting sediment samples in the United States, and
FISP-developed samplers have been used by the World Meteorological
Organization as controls for comparison with suspended-sediment samplers
developed in several foreign countries. Given its history (Skinner,
1989), interagency composition, and functions, the FISP represents a
logical focal point for management of the SMIARP.

Proliferation of sediment-surrogate monitoring technologies (Wren and
others 2000) primarily through private enterprise and universities,
makes it likely that commercially produced devices will constitute the
bulk of instruments that may eventually be applied for measuring fluvial
sediments (Gray and Schmidt, 2001). Hence, it makes considerable sense
for the private sector and universities to have the opportunity to
participate in the SMIARP to provide and receive guidance. Additionally,
participation of other countries---governments, international
associations, or the private sector---should only serve to strengthen
and enhance and perhaps help support the SMIARP.

###### SUMMARY

In response to expanding needs for fluvial-sediment data concomitant
with declines in sediment-data acquisition, formation of a Sediment
Monitoring Instrument and Analysis Research Program has been
recommended. A SMIARP would foster research, testing, and evaluations on
instruments and methods for measuring, monitoring, analyzing (including
computing, and estimating) selected characteristics of fluvial sediments
in cost-effective, safe, and quantifiably accurate means. If the Federal
Interagency Subcommittee on Sedimentation accepts the recommendation
from the Federal Interagency Workshop on Turbidity and Other Sediment
Surrogates to form a SMIARP, delegation of SMIARP oversight to the FISP
should be considered as a management option.

**REFERENCES**

ASTM International, 2003, Home Page: Accessed May 21, 2003, at
www.astm.com.

Edwards, T.K., and Glysson, G.D, 1999, Field methods for measurement of
fluvial sediment:

U.S. Geological Survey Techniques of Water-Resources Investigations Book
3, Chapter 2, 89 p. Accessed June 12, 2003 at
http://water.usgs.gov/osw/techniques/sedimentpubs.html.

Federal Interagency Sedimentation Project, 2003, Home Page: Accessed
August 6, 2003 at http://fisp.wes.army.mil/.

Glysson, G.D., and Gray, J.R., 1997. Coordination and standardization of
Federal sedimentation activities: Proceedings of the U.S. Geological
Survey Sediment Workshop, February 4-7, 1997. Accessed May 20, 2003 at
http://water.usgs.gov/osw/techniques/workshop/glysson.html.

Gray, J.R., 2002, The need for sediment surrogate technologies to
monitor fluvial-sediment

Transport: Proceedings of the Turbidity and Other Sediment Surrogates
Workshop, April 30 - May 2, 2002, Silver Legacy Hotel, Reno, Nevada, 4
p. Accessed May 20, 2003 at
http://water.usgs.gov/osw/techniques/TSS/listofabstracts.htm.

Gray, J.R, and Glysson, G.D., 2003, Proceedings of the Federal
Interagency Sedimentation Workshop on Turbidity and Other Sediment
Surrogates, April 30-May 2, 2002, Reno, Nevada. U.S. Geological Circular
1250. Accessed August 8, 2003 at
http://water.usgs.gov/osw/techniques/turbidity.html.

Gray, J.R., Glysson, G.D., and Mueller, D.S., 2002, Comparability and
accuracy of fluvial-

sediment data---A view from the U.S. Geological Survey: Proceedings of
the American Society of Civil Engineers, Hydraulic Measurements and
Methods Symposium, July-August, 2002, Estes Park, CO, 6 p. Accessed May
20, 2003 at http://water.usgs.gov/osw/techniques/asce.pdf.

Gray, J.R., and Schmidt, L.J., 2001, Sediment-data quality,
availability, and emerging technology---A discussion: Proceedings of the
Gravel-Bed Rivers V Workshop, edited for the New Zealand Hydrological
Society by M. Paul Mosley, pp. 369-373.

International Standards Organization, 2003, Home Page: Accessed July 24,
2003 at http://www.iso.org/iso/en/ISOOnline.openerpage.

Skinner, J. V., 1989, History of the Federal Interagency Sedimentation
Project, in, Proceedings of the International Symposium, Sediment
Transport Modeling: Sam S.Y. Wang, ed.: American Society of Civil
Engineers, New Orleans, August 14-18, 1989, pp. 266-271.

U.S. Environmental Protection Agency, 2002, National water quality
inventory - 2000 report: EPA-841-R-02-001. Accessed May 20, 2003 at
http://www.epa.gov/305b/2000report/chp2.pdf.

U.S. Environmental Protection Agency, 2003, Total maximum daily loads.
Accessed May 22, 2003 at
http://www.epa.gov/ebtpages/watewaterptotalmaximumdailyloadstmdls.html.

U.S. Geological Survey, 2002, Turbidity and Other Sediment Surrogates
Workshop: Federal Interagency Subcommittee on Sedimentation. Accessed
May 20, 2003 at http://water.usgs.gov/osw/techniques/turbidity.html.

Wren, D.G., Barkdoll, B.D., Kuhnle, R.A., and Derrow, R.W., 2000, Field
techniques for suspended-sediment measurement: American Society of Civil
Engineers, Journal of Hydraulic Engineering, Vol. 126, No. 2, pp.
97-104.