Rebirth of Water Report 2016-2017

4.2 Water Quality Parameters Analysis B
The water quality monitoring of the Lower Marsh Creek had the objective of monitoring certain
parameters over the summers from 2012 to 2016. While none of the sites were, on average, below the
Canadian guidelines of 200 CFU/100 mL for recreational waters, this year saw a dramatic decrease in
fecal coliform count in sites 1 and 4 (Task Force, 1994). In comparison to previous years, 2016 is
characterized by a more uniform count of fecal coliform between sites 1, 2, 4 and 5. With the exception
of 2015, the trend at site 3 continues to be to have approximately 25000 to 50000 CFU/100mL. Site 3
continues to have a high occurrence of waterfowl; Canada geese and mallard ducks were seen with their
young each sampling period. It is likely that site 3 will continue to have a higher fecal coliform count due
to these external factors. Although the averages were above the Canadian guidelines, 2016 data was
consistent with 2014 and 2015 and saw several individual occurrences where fecal coliforms were within
the Canadian guidelines for recreational water at particular sites (Appendix C).
The monitored portion of Marsh Creek is considered non-salmonid water and the Canadian Water
Quality Guidelines indicate dissolved oxygen levels are to be greater than 6.5 ppm. A moderate
impairment is experienced by these fishes at 4 ppm and death at 3.5 ppm (Task Force, 1994; 3-14). As
seen in Appendix L, Table L-1, from 2012 to 2015 dissolved oxygen levels moved from a level where
fish survival was not even possible in some areas to Marsh Creek DO levels all above the recommended
guidelines. The results from 2016 revealed that since the previous year, all sites except site 1 had a decrease
in dissolved oxygen. Sites 1 through 4 maintained average dissolved oxygen levels above 6.5 ppm;
however, site 5 fell below 6.5 ppm. This trend was coupled with a roughly 2°C increase in average
temperature at all sites from 2015. These parameters may have been affected by the drier than usual
summer; the Canadian Agriculture and Agri-food Department assessed southern New Brunswick as
having an abnormally dry summer (Government of Canada, 2016). Studies have connected surface water
temperature increase and dissolved oxygen concentration decrease during periods of drought (Murdock
et al., 2000; Van Vliet and Zwolsman, 2008).
Due to changes in the procedure for total phosphates, results for all sites from 2016 were on average
higher than results from 2015. To confirm the accuracy of the new procedure, a control was used and
phosphate concentrations were determined to be roughly double of what they would have been using
the previous method. Although higher, there was no drastic change seen when compared to 2015,
suggesting the levels of orthophosphates were potentially lower than previous years.
Since 2014, toilet paper and other toiletry debris could no longer be seen floating down Marsh Creek as
raw sewage inflow has ceased. By testing for total suspended solids, it was possible to determine the
concentration of the remaining floating debris. The Canadian water quality guidelines indicate TSS has
no harmful effect if less than 25 mg/L and concentrations from 80-400 mg/L are not ideal for fish life
(Task Force, 1994; 3-42). Table 3.1.C. shows average TSS for 2016 were once again less than 25 mg/L.
From 2012 to 2014, the average pH had been within the recommended guideline of 6 to 8. In 2015, it
was found on average pH had decreased and site 3 and 4 had reached between 8 and 9. In 2016, all sites
except site 3 were between a pH of 7-8.
The Marsh Creek watershed experiences salinity intrusion through the tide gates of the Courtenay Bay
Causeway. As seen in Figure 3.1.E., the samples taken showed higher values for salinity at the two sites
nearest the tide gates. This was expected due to the heavy tide influence experienced by Marsh Creek.
The fluctuation seen at the sites nearest the gate from one year to the next could be due to a potential
difference in sampling times in reference to high or low tide.
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