Meeting papers

                                                                 Burgess Creek Monitoring Program
                                                                                      Annual Review 2022



5.5 Long term variability

Figure 39 to Figure 52 shows the long-term variability of microbiological and nutrient
indicators measured at each monitoring site from 2015 to 2021. Where no samples were
collected, no value is shown. As per recommendations in the 2017 and 2020 Annual
Monitoring Report, longer-term assessment using historical monitoring data has been
included to depict any apparent temporal or spatial trends in the data sets and potential
influences of the treated wastewater release. These figures present the long-term
measurements        collected    for   microbiological      indicators    (E.coli,   Enterococci   and
Thermotolerant Coliform) and key nutrient indicators (Total Phosphorus, Total Nitrogen and
Chlorophyll a) across all monitoring sites.

The following trends were noted in the monitoring data:

    •   E.coli has no clear long-term trend within the data collected from any of the
        monitoring sites with the exception of B8 which shows increasing concentration with
        time.

    •   Thermotolerant coliforms have a decreasing long-term trend at monitoring site
        SW3. Monitoring site B3, B8, B5 and B6 have an increasing trend and monitoring
        site B1 and B2 showed no clear long-term trend within the data collected from 2015
        to 2021.

    •   Enterococci had an increasing long-term trend at monitoring sites B8. Monitoring
        site B2, B5, B6 and SW3 have a decreasing trend and monitoring site B3 and B1
        and showed no clear long-term trend within the data collected from 2015 to 2021.

    •   Total phosphorus and ammonia have no clear long-term trend within the data
        collected from any of the monitoring sites.

    •   Total Nitrogen has a decreasing long-term trend at monitoring site SW3. Monitoring
        site B1, B3, B5, B6 and B8 have an increasing trend and monitoring site B2 showed
        no clear long-term trend within the long term data collected.




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