Overall, river flow during the fall has been very low and high salinity is still firmly in place. On 29 November, salinity still exceeded 20 in the lower parts of the estuary. The estuary was weakly stratified except in the upper estuary where the difference between surface and bottom salinity was approximately 10. At the head of the estuary at Streets Ferry Bridge (station 0), bottom water salinity set an all time ModMon record of 11.95 beating the previous record of 11.27 set in Dec. 2007. Dissolved oxygen was > 8 mg/L except in the highly stratified wates at Streets Ferry Bridge where bottom water dissolved oxygen was ~ 3 mg/L. Chlorophyll was generally less than 10 ug/L throughout the estuary with the exceptoin of a near surface maximum at station 30. Microscopic examination of station 30 surface water revealed a phytoplankton community dominated by the dinoflagellate, Prorocentrum minimum. P. minimum is the most common cool-weather, bloom-forming dinoflagellate in the Neuse. It’s not toxic and hasn’t been associated with fish kills. Turbidity was less than 5 NTU throughout the estuary. The monitoring crew is on the Neuse again today, so we’ll provide one more summary of conditions before the holiday break.
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