determine the average annual sediment discharge. To determine the average annual total

bed-material discharge the computer model is used to determine the bed-material discharge

for a range of discharges to develop a sediment discharge rating curve or table. This rating

curve is used in combination with a flow duration curve or table to determine the average

annual bed-material discharge. BRI-STARS can be used for single event or long-term

sediment transport simulations, whereas HEC-6 is better suited for long-term simulations and

should be used with caution for single event simulations.

The U.S. Army Corps of Engineers SAM package (Thomas et al. 2000) includes sediment

transport calculations using a wide variety of equations. The SAM package uses normal

depth hydraulics and does not perform sediment routing. It is intended for basic sediment

transport analysis and for developing sediment rating curves as part of a sediment yield

analysis.

The following example problems illustrate the application of concepts and equations for

sediment transport. Because several of the equations are commonly given in English units

(for example Einstein's equation) and the methodology is very complex, some of the

examples will only be given in English units. Readers who use metric units (SI) are

encouraged when encountering similar problems to convert the input variables to English

units, solve the problem, and convert the results back to SI units.

From data observed on the Missouri River, calculate the vertical suspended sediment

concentration profile for the D50 sediment size in mg/l.

Given:

y o = 4.30 m

V = 1.27 m / s

S = 0.000210

Temp = 22.5C (72.5F)

D50 = 0.000255 m

ω (D 50 ) = 0.0338 m / s

υ = 1.00 x 10 -6 m2 / s

c a = 775,000 mg / l

From Equation 4.12:

Z

y - y

a

ω

c

= o

and z =

yo - a

βκV*

ca y

4.37

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