Development of a Depth-Integrated Sample Arm to Reduce Solids ...

Selbig and Bannerman
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Specific Density, in g/CM(
Figure 5---Cumulative distribution of average specific density estimated in the fixed-point and lower, middle, and
upper DISA samples [(n) = number of samples used in analysis].
become important in poorly mixed flows. Therefore, proper Horowitz (1995) reported increasing concentrations of sediment
characterization of the distribution of particles in urban runoff with increasing depth in fluvial systems. The data presented in
requires the collection of water quality samples from multiple Figures 6 and 7 illustrate a similar trend in a storm sewer. The
points, rather than from a single fixed point in the water column. increase in concentration is the result, in part, of an increase in
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organic Content, In percent
Figure 6-Relationship of the percent organic material in samples collected from the lower, middle, and upper DISA
sample locations with the depth of water in the storm sewer at the residential study site.
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Water Environment Research, Volume 83, Number 4