Discussion

        With the exception of total suspended solids, the relocation of Mason Inlet has not led to any adverse water quality impacts in Mason Creek or other nearby locations.  State-regulated water quality parameters including turbidity, chlorophyll a, and fecal coliform bacteria counts showed few violations of North Carolina State standards either before or after inlet relocation, and dissolved oxygen remained well within required limits at all times.  Total suspended solids concentrations doubled at four out of the five stations following project completion.  We suspect that this was due to the higher energy entering the system from the new inlet having greater ability to move the sand particles around.  Since turbidity and chlorophyll a remained low after dredging, the TSS measurements consisted primarily of sand particles that are individually large but do not unduly cloud the upper water column.  Observations of the rapid filling in of Banks Channel and Mason Creek following dredging tend to support this speculation.

        The water quality of Howe Creek has likewise not had any ill effects from the Mason Inlet project.  In fact, the uppermost station has demonstrated a decrease in fecal coliform counts.  Since salinity during the coliform collections was actually lower following inlet relocation, the decrease in the upper watershed was likely not related to the dredging project, but to rainfall variability and localized runoff patterns.  UNCW is continuing its sampling program in Howe Creek to follow water quality fluctuations, especially in light of the new development activity along Military Cutoff and its potential effect on upper Howe Creek.