Meeting papers

                                                                 Burgess Creek Monitoring Program
                                                                                  Annual Review 2022



5.4 Temporal Variability

.
Figure 23 to Figure 38 shows the variability of water quality parameters measured at each
monitoring site in the 2021 calendar year. Where no samples were collected, no value is
shown. It should be noted that:
        •    Monitoring site B8 has no data for March, April, June, July, August, September,
             October, November, and December 2021.

        •    Monitoring Site B5 has no data for July 2021.

The following trends were noted in the concentration of the following water quality
parameters:
    •       Higher microbiological indicator (E.coli, enterococci and faecal coliforms) levels at
            several sites (particularly B1, B2, B5, B6, B8 and SW3) following periods of high
            intensity rainfall events.

    •       Ammonia at B8 remained low throughout the year with the exception of a spike in
            December for all monitoring sites apart from B2.

    •       Nitrate & Nitrite (NOx), was highly variable throughout the year (except for B2 and B8
            remaining low throughout).

    •       A peak in total nitrogen occurred at B1 in March prior to a decrease in concentration
            below B3, B6 and B5 for the remainder of the year. The other sites were consistent
            throughout the year.

    •       Filter reactive phosphorus and total phosphorus had a spike in concentration at most
            sites in February (except for B2 and B8).

    •       Dissolved Oxygen remained relatively consistent with only slight variability at all
            monitoring sites, except for B5 which spiked in June.

    •       pH remained constant throughout the year with all sites remaining between 6.5 and 8
            pH units, except for B2 and B8 which remained below 6 pH units.

    •       Conductivity for most monitoring sites (except for B2 and B8) fell in May and spiked in
            November.

    •       Chlorophyll a varied throughout the year with a notable spike at B8 in May.

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