August 2024: Chemical, Water Quality and Macroinvertebrate Analysis

Alison Loxton
Sep 27, 2024
2 min read

Hi everyone

I trust this email finds you well, mentally as well as physically.

The results for August are attached, with the following observations offered for your consideration:

Overall, the results for temperature are consistent with the exception of Regatta Waters where the water temperature was a good 4 – 5 degrees lower than other readings. Not sure why this is so, unless the two pumps exchanging water with the Coomera River are not fully functional.
pH readings were generally a little less than neutral (7) and some were distinctly alkaline, particularly in the saltwater. This is normal.
Salinity was variable; despite the lack of rain the readings were not as high as in summer, with the highest reading 32.9 ppt whereas in summer this would be approaching 40ppt under similar climate conditions. The salinity in Regatta Waters was much higher than the adjacent Coomera River, which adds further weight to the suggestion that perhaps water exchanges with the river itself were less that we are used to.
Dissolved Oxygen measurements were generally quite supportive of aquatic life, even in Waterhen Lake; the exception is Site 1 which receives the runoff from Ruth Terrace. If there is no runoff there is no flow and D.O levels are down; the wind does not affect the D.O at that site as it does in the main area of the lake.
In terms of chemical analysis, the greatest variation occurred with phosphates in Site 2 at Regatta Waters where, I suspect, the early spring weather caused people to be out fertilizing their gardens, with the runoff straight into the stormwater pipe adjacent to the sampling site.
Chemical readings for Ammonia Nitrogen were most pleasing, with the readings in Waterhen lake within their normal range.

Overall, our waterways are in quite good condition, even the freshwater ones which is great news.

We will enjoy our final planting for the year on the 12th of October. You are most welcome to join us, and I understand there will some Indian treats on offer as a break from the usual scones and cupcakes. So come along and join in the fun and the social interactions to follow.

My kindest regards to you all and looking forward to seeing your smiling faces

Steven Gill