Application of the modified Einstein procedure for computation of total sediment load

Schroeder, Kenneth B.; Hembree, C. H.

doi:10.1029/tr037i002p00197

Cited by 6 publications

(3 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…, 1992). Using the method of Colby & Hembree (1955), Schroeder & Hembree (1956) reported suspended load fractions between 28% and 79% of the load measured upstream of the sampling point at a constricted section (assumed to represent the total load) for transport in the Niobrara River on individual days. For the yearly sediment loads at the Nigardsbreen glacier, the fraction of sediment transported in suspension varied between 24% and 61% (Kjeldsen, 1974, 1975, 1977, 1981, 1983; Bogen, 1989; Hallet et al.…”

Section: Long‐term Partitioning Of Suspended Load and Bedloadmentioning

confidence: 99%

The partitioning of the total sediment load of a river into suspended load and bedload: a review of empirical data

2010

View full text Add to dashboard Cite

The partitioning of the total sediment load of a river into suspended load and bedload is an important problem in fluvial geomorphology, sedimentation engineering and sedimentology. Bedload transport rates are notoriously hard to measure and, at many sites, only suspended load data are available. Often the bedload fraction is estimated with 'rule of thumb' methods such as Maddock's Table, which are inadequately field-tested. Here, the partitioning of sediment load for the Pitzbach is discussed, an Austrian mountain stream for which high temporal resolution data on both bedload and suspended load are available. The available data show large scatter on all scales. The fraction of the total load transported in suspension may vary between zero and one at the Pitzbach, while its average decreases with rising discharge (i.e. bedload transport is more important during floods). Existing data on short-term and long-term partitioning is reviewed and an empirical equation to estimate bedload transport rates from measured suspended load transport rates is suggested. The partitioning averaged over a flood can vary strongly from event to event. Similar variations may occur in the year-to-year averages. Using published simultaneous short-term field measurements of bedload and suspended load transport rates, Maddock's Table is reviewed and updated. Long-term average partitioning could be a function of the catchment geology, the fraction of the catchment covered by glaciers and the extent of forest, but the available data are insufficient to draw final conclusions. At a given drainage area, scatter is large, but the data show a minimal fraction of sediment transported in suspended load, which increases with increasing drainage area and with decreasing rock strength for gravel-bed rivers, whereby in large catchments the bedload fraction is insignificant at ca 1%. For sand-bed rivers, the bedload fraction may be substantial (30% to 50%) even for large catchments. However, available data are scarce and of varying quality. Longterm partitioning varies widely among catchments and the available data are currently not sufficient to discriminate control parameters effectively.

show abstract

Section: Long‐term Partitioning Of Suspended Load and Bedloadmentioning

confidence: 99%

The partitioning of the total sediment load of a river into suspended load and bedload: a review of empirical data

2010

View full text Add to dashboard Cite

show abstract

“…Geological Survey from 1947 to 1953, actual comparisons were made between measured and computed sediment discharges for various small Nebraskan streams (COLBY and HEMBREE, 1955;SCHROEDER and HEMBREE, 1956;HUBBELL and MATEJKA, 1959). Considerable care was exercised in measuring the sediment load, taking advantage of naturally constricted sections on some streams in which velocities were high enough to keep the entire load in suspension, while on one stream a turbulence flume was constructed for the purpose of creating sufficient turbulence to support the sediment load.…”

Section: Mod$ed Einstein Proceduresmentioning

confidence: 99%

Measurement of Sand Transport in Rivers With Special Reference to Tracer Methods

Crickmore

1967

Sedimentology

View full text Add to dashboard Cite

SUMMARY The paper describes tests made on a small river to examine the practicability of measuring quantitatively, by tracer methods, sand transport occurring over a rippled bed in a natural channel. Three principal tracer methods, all previously verified under steady flow conditions in a laboratory channel, and identified as the spatial integration, time integration and steady dilution methods, were examined by introducing radioactive and fluorescent tracers to represent a narrow size fraction of the bed sand. The serious limitations of the time integration and steady dilution methods under conditions of unsteady solids discharge were exposed by a sudden flood discharge occurring during the course of the study. An approximate method, based on the time integration approach, but also requiring some spatial tracer data, is suggested, whereby an estimate of the transport is possible in the case of highly variable sand discharge. However, it is seen that in the sand case, the spatial integration method offers the most workable and informative tracer method for use in natural rivers. The results, by this method, were generally consistent with those given by the summation of the measured suspended‐solids flux and the transport occurring either by surface creep or in close vicinity to the bed. The latter quantity is determined from the downstream advance of the ripple bed‐forms, and methods are described for its derivation from ultrasonic echo sounder records of bed profiles. Finally sand transport values are calculated for a number of river discharges and for two laboratory channel tests using various well‐known computational procedures—Einstein, Bagnold, modified Einstein, Meyer‐Peter and Muller, and Laursen procedures. Significant differences in the computed values for individual flow conditions are observed.

show abstract

“…Einstein (1950) has stated the theories on which the method is based, and Colby and Hembree (1955, p. 66-98) have explained the reasoning, assumptions, and experimental basis from which the modified procedure was developed. Accuracy and consistency of total sediment discharges that have been computed with the modified Einstein procedure have been discussed by Schroeder and Hembree (1956), Hubbell and Matejka (1959), and Colby and Hembree (1955, p. 106-113).…”

Section: Simplified Methods Of Computationmentioning

confidence: 99%

Simplified methods for computing total sediment discharge with the modified Einstein procedure

Colby¹,

Hubbell²

1957

Open-File Report

View full text Add to dashboard Cite

show abstract

Application of the modified Einstein procedure for computation of total sediment load

Cited by 6 publications

References 4 publications

The partitioning of the total sediment load of a river into suspended load and bedload: a review of empirical data

The partitioning of the total sediment load of a river into suspended load and bedload: a review of empirical data

Measurement of Sand Transport in Rivers With Special Reference to Tracer Methods

Simplified methods for computing total sediment discharge with the modified Einstein procedure

Contact Info

Product

Resources

About