10.0  Pages Creek

            Pages Creek was sampled at three stations, two of which receive drainage from developed areas near Bayshore Drive (PC-BDUS and PC-BDDS - Fig. 10.1).  During the past sample year turbidity was low with no incidents of turbidity exceeding the state standard of 25 NTU (Table 10.1).  However, there were a few incidents of hypoxia during summers of 2003 and 2004, two each at the stations draining Bayshore Drive (Appendix B).  Fecal coliform bacteria were not sampled at this creek during the past year.  Nitrate and orthophosphate concentrations showed a notable increase over the previous year, although phytoplankton biomass as chlorophyll a was low with no algal blooms noted (Table 10.1).  Median inorganic nitrogen-to-phosphorus molar ratios were well below 16, indicating that phytoplankton growth in this creek is probably nitrogen limited.   Because of the relatively low watershed development and low amount of impervious surface coverage in the watershed (Mallin et al. 1998a; 2000b), this is one of the least-polluted tidal creeks in New Hanover County. 

Table 10.1.  Selected water quality parameters in Pages Creek as mean (standard deviation) / range, August 2003-July 2004.
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Parameter                              PC-M                          PC-BDDS                  PC-BDUS
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Salinity (ppt)                          34.4 (2.2)                   30.2 (7.1)                   16.5 (11.4)
                                                30.2-38.4                   11.0-36.3                   1.2-34.1

Turbidity (NTU)                      5 (3)                            6 (4)                             9 (6)
                                               1-9                              1-14                             3-23

DO (mg/L)                             7.6 (2.0)                      7.3 (2.3)                      7.4 (2.0)
                                               5.2-10.6                      4.1-10.6                      4.5-10.6

Nitrate (mg/L)                       0.008(0.003)              0.036(0.035)              0.035(0.024)
                                               0.004-0.017               0.004-0.108               0.004-0.074

Ammonium (mg/L)               0.016(0.007)              0.032(0.029)             0.046(0.020)
                                               0.008-0.034               0.008-0.106               0.008-0.068

Orthophosphate (mg/L)       0.008(0.003)              0.013(0.007)              0.019(0.010)
                                               0.005-0.015               0.006-0.026              0.005-0.038  

Mean N/P Ratio                    6.9                               11.7                            10.7   
median                                   6.6                                 9.5                             9.2

Chlor a (mg/L)                       1.4 (0.7)                      3.6 (3.3)                      4.2 (4.0)
                                                0.3-2.4                        0.5-9.4                        0.8-13.5
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