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Thursday, 02 May 2024 04:07

Norman Griffiths Oval synthetic turf installation has become a debacle

Construction of the synthetic turf field at Norman Griffiths Oval in Bicentennial Park, West Pymble commenced in August 2023. You will recall the controversy about the use of this site for synthetic turf with its proximity to Sydney Turpentine Ironbark Forest and Quarry Creek, the waterway that runs under the field and flows through to Lane Cove National Park. The bushland along the creek has been transformed by bush carers working over many years.

One major issue with the choice of this location for synthetic turf is that the field acts as a stormwater detention basin. Water from rainfall events runs from the surrounding slopes into the field and into pipes and a detention system then would gradually drain ultimately into Quarry Creek at various locations. There was also a pipe running under the field taking water from the nursery on the other side of Lofberg Road into the detention system.

The installation of synthetic turf creates an area where rainwater can seep through but heavy rain will flow rapidly across the field and into Quarry Creek. Flood models were commissioned that determined that a new drainage system was required. This comprises a large area of porous aggregate which allows for vertical, filtered drainage and stormwater detention. Once the water has filtered through this detention basin it will go into a bio-retention basin where it then flows gradually into the current stormwater pipe system under the aquatic centre carpark.

There have been repeated incidents of muddy water running down Quarry Creek usually after rain since construction started. It seems the runoff from the field is not being controlled. A broken pipe is blamed so the detention system is not working. The EPA is investigating.

Now the stage of construction has been reached where there are large piles of aggregate and dirt across the site. Then there was very heavy rain on 5 and 6 April with over 200 mL. The construction site became a lake as it seems there was too much water for the drainage system (see image at the top of the page).

There have been repeated episodes of muddy water in Quarry Creek but the latest incident is the worst. A solution has to be found to pump out the water from the muddy lake. It can’t go down Quarry Creek. There is already a build-up of silt on the bed of the creek. We are trying to find out who is responsible for cleaning this up.

Meanwhile construction activity has ceased.


Muddy water flow into Quarry Creek, 150 m from oval, 6 Nov 2023