CHANGES IN SEDIMENT LOADING OVER TIME ON AN ACTIVE MILITARY TRAINING FACILITY

Turbidity was monitored from 2002 to 2014 on an active military training base to study the impact of this land use change on the health of watersheds within the facility. Turbidity, discharge, and stage data were recorded over a 9-year period in two study sites to assess stream sediment loads and to monitor seasonal and episodic changes in sediment load, and thus, water quality. Loggers with turbidity probes were placed in both of these stream sites to collect the data for the study, and a water level gauge was used to collect stage data. Discharge was calculated from the stage data. Total load calculations using discharge, turbidity, and a regression correlation were used to find the mass of the sediment entering the two stream sites. Turbidity and discharge data were cross correlated to discharge using MATLAB for each water year to assess the data for lags in turbidity storm response and to look for a change in overall stream response to sediment load over time. The MATLAB correlation plots yielded similar curves for 2008 and 2014 water year data. No changes were observed in lag time or overall shape of the correlation plots. Variations in timing of turbidity response were attributed to variations in seasonal rainfall from year to year. This result shows that little change in stream behavior has occurred over this 6-year period. Despite variations in rainfall and storm intensity from year to year, the discharge and turbidity correlation appears to remain steady over long periods of time.