Date of Award

Winter 2008

Project Type


Program or Major

Civil Engineering

Degree Name

Master of Science

First Advisor

Thomas Ballesterro


This research examined several methods for monitoring suspended sediment concentration and particle size in stormwater runoff.

Suspended sediment concentration was monitored using the following methods: automatic sampling reported as Suspended Sediment Concentration (SSC), automatic sampling reported as Total Suspended Solids (TSS), turbidity reported as SSC and turbidity reported as TSS. Particle size distribution (PSD) was measured in samples from automatic samplers using tri-laser diffraction. An entire volume of the discharge passing by the automatic samplers and turbidity meter was captured and presumably contained the actual values to which all other methodologies were compared.

Automatic sampling with SSC proved to be the most accurate in representing the actual suspended sediment concentration. The TSS method's accuracy suffered during events with high discharge rates. Turbidity was not found to be an accurate measure to represent suspended sediment concentration. Automatic samplers collected samples containing sand size sediments but did not have a representative PSD.