Meeting papers

                                                                                      Burgess Creek
                                                 Receiving Environment Monitoring Program
                                                                                 Annual Review 2022
situated in an ephemeral section of the Creek, which only contains surface water during and
immediately following rainfall, leading to an absence of water for most of the year, making it
difficult to collect water quality samples. Ongoing surface water monitoring above B3 poses
a significant challenge that may prove difficult to address. The impact of decreased surface
water flows, resulting from climatic variability, will be more pronounced in the West branch
above B3. This is because historical activities, such as residential and waste disposal
practices, have disrupted the creek's natural hydrology and soil composition. In contrast, the
hydrology and natural state of the East branch within the Noosa National Park have been
preserved, resulting in surface water remaining present throughout the year.

In 2021, the western section of Burgess Creek was primarily composed of treated wastewater
releases from the Noosa STP, as almost all the flow within this section was attributed to this
source. The Sampling Officers currently use subjective estimation methods to determine the
water flow within Burgess Creek, although this approach does not provide a quantitative
measurement, it is known from historical data that monitoring site B8 does not complete all 12
sampling events. In 2021, flow was observed during only 3 of the 12 sampling events,
indicating that the western branch of Burgess Creek would have experienced few flow events
without the presence of Noosa STP treated wastewater releases. Unlike discontinued
monitoring site B4, monitoring site B8 is not affected by siltation and overgrown nature of the
channel. B8 is situated on a significant waterway that originates from the Melaleuca Forest
community, and experiences occasional waterlogging, which can impact the flow and quality
of water within the channel.

The results indicate that water stagnation may have occurred at B8 due to the low or no water
flow for a significant portion of the year. This is evidenced by the higher ammonia
concentrations observed at B8 compared to the other sites within the Catchment, where
ammonia concentrations remained consistent. The observed increase in ammonia
concentrations at B8 can be attributed to the lack of turbulence, which reduces volatilization
and increases the accumulation of metabolic waste and decomposition products, as per the
findings of Suter et al. (2021).

It is found that the B8 monitoring site above the Noosa STP Outfall continues to be the most
suitable location. However, the present parameters employed for estimating or measuring
water flow within the western branch are insufficient. The transient nature of the western
branch is a hindrance in obtaining accurate flow measurements. The absence of accurate flow
monitoring in this area is posing difficulties in ensuring consistency with the strategy
implemented two decades ago and coping with natural climate drivers and changes in rainfall

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