Water Quality

WaterTesting1

A good indicator of the health of a catchment is the quality of the water that flows out the lower end. With this in mind, our Landcare group has been part of the Streamwatch programme, now with the Greater Sydney Landcare Network, for over 12 years. In turn, this is part of the Australia-wide Waterwatch water quality monitoring program.

 Is it safe to paddle in our local creeks?

Still Creek Landcare have tested the water quality monthly for 12 years in three local locations: Charltons Creek; Still Creek at Mansfield Rd and Still Creek at Crosslands, after the various tributaries have joined. We test for:

  • Excess nutrients from fertilisers and waste water: Phosphates test
  • Salts from human activities and waste water: Electrical conductivity test
  • Faecal bacteria from human, livestock and other animal shit: E. coli test
  • Sediment from erosion of soil due to animals, building, earth moving: Turbidity test
  • Life in the water depends on the oxygen level: Dissolved Oxygen test
  • Life itself in the water: inspect for presence of macroinvertebrate creatures

The condition of these waterways has not deteriorated over the last 12 years, although there has been an increase in E. coli detection in the last 18 months, but not to high levels. So we should all watch our waste water treatment systems and keep animal waste from lying around to seep into the creeks.

Based on our test results, these waters are clean enough to paddle in most of the time, but not after heavy rain and during high water flows because at those times more runoff occurs and more stuff gets washed in.

Over the last year we have worked with Hornsby Shire Council and three other Streamwatch groups in the area to check our testing against the council professionals. The results have less accuracy, but are of use for long term monitoring and pollution incident reporting.

Water Quality brochure

For information on our water quality, what we test for, the sources of pollution and what we can do to help, please see our Clean Waterways  brochure

What have we found?

  • Water tests have shown that the catchment is in good condition and that general water quality has being maintained over the last 12 years
  • On exit from the catchment into Berowra Creek at Crosslands most results are good with the areas of bush and the dilution effect improving the water as it flows through the catchment
  • Further upstream in the catchment, closer to residences, results are not as good, but are not a major problem
  • Charltons Creek , high in the catchment, tends to be high in phosphorous, with quite notable surges after heavy rain
  • Still Creek in mid-catchment at Mansfield Road is high in salts, as measured by electrical conductivity tests and shows a large variation, with a long flat tail
  • E coli incidence is low but has increased significantly over the last 18 months
  • Waterbug (Macroinvertebrates) observations have found Mayflies, Caddisflies at sometimes Stoneflies at both Charltons Ck and Still Ck Crosslands
  • See these articles on the waterbugs: Tiny Creatures in Our Creeks and Life in Local Waterways

Map of Test Sites.

On a regular basis, testing is completed at 3 fixed sites each month. Other sites in the catchment have also been tested and we are willing to test sites on request of landowners.

Recent Water Test Results

Our Conclusions

Site Summary

Frequency Distribution for Electrical Conductivity, Available Phosphate and Dissolved Oxygen with Flow

Water Quality – Time Series

Raw Data Catchment Exit

Raw Data Mid Catchment

Changes in 4 Year groupings

Effect of Rain

E. coli

Waterbugs

 

Article in Galston, Glenorie & Hills Rural Community News Mar 16 on Water Testing

Article in Galston, Glenorie & Hills Rural Community News Feb 17 on the Importance of Water

Article in Community News on Citizen Science Water Testing in Glenorie

Article in Galston, Glenorie & Hills Rural Community News Apr 18 on Water Testing