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

Selbig and Bannerman
sand-sized material. In the absence of turbulent eddies, coarse
particles with high specific density become stratified and tend to
be transported along the bottom of the pipe floor. As the energy of
flow in the pipe increases, sediment concentration and particle
size also increase. However, the distribution of coarse particles
may remain stratified. Figures 7a and 7b show the distribution of
particles in water samples collected during the rising limb and
peak of a storm hydrograph at the parking lot study area. Plots of
the lower, middle, and upper sub-samples are shown with
corresponding fixed-point samples to highlight changing distributions
with water depth. Mean concentrations of suspended
sediment for the DISA and fixed-point samplers also are shown to
provide a correlation and comparison of sediment concentration
and particle size with discharge (energy). At the onset of flow in
the pipe, when discharge is low, particles are relatively small in
diameter (d50