August 2026: Chemical, Water Quality and Macroinvertebrate Analysis

Alison Loxton

Oct 4

2 min read

Hi to our valued members

This month are two items for consideration: the WQM results, and the two plantings scheduled for October 2026.

Water Quality Monitoring results.

Attached are the results for the saltwater reaches of the Coomera River, plus Waterhen Lake.

The following comments are offered for your consideration:

Due to the lack of rainfall, salinity is as high as normally occurs in the Coomera River: 38.61 ppt at Paradise Point tapering down to 20.2 ppt at the causeway.
Unlike previous times there is now a significant discrepancy in salinity between the main river and Regatta Waters – 31ppt at Koala Town Road as opposed to 26ppt at Regatta Waters. Perhaps the water pumps are not working as frequently as they used to.
Water temperatures in Regatta Waters are around two degrees lower than that of the main river.
There was a spike in reactive phosphate readings in Regatta Waters and at the causeway.

In Regatta Waters one possible explanation could be that people fertilized their garden ahead of forecast rain which did not eventuate, then had to water by hand. This often results in more water being used, and the nutrient rich runoff ending up in the lake.

With the prevailing southwesterly to southeasterly winds the nutrients would have been driven to the northern side of the lake, hence the higher readings at sites three and four.

At the causeway the low flow level allows nutrients to accumulate.

It is most gratifying to see that ammonia nitrogen levels are staying low, a result no doubt of vigilance around sewage and septic tank maintenance.

We are experiencing what is for us a prolonged dry period, the only antidote for which is a serious amount of rainfall to replenish water tables and to restore river and stream levels.

Plantings

We will conduct our last planting for this year on Saturday 10^th October 2026. This is at our normal site at Regatta Waters Park and will commence at 8am.
We also have the exciting opportunity to join a planting at Wongawallan on Saturday 24^th October 2026 hosted by Naturally GC. I did redirect an email from Marcello inviting us to join this planting however we must register as positions will be allocated on a first in first served basis. If you want a fresh copy of the email just let me know.

Trusting this email finds you all safe and well.

Kind regards

Steven