Last weekend we were driving down President Avenue towards Brighton Le Sands & I did as I always do & looked at Scarborough Park on the way past. I saw something in the pond that made me decide to stop there at the end of the day. And we did.
I love Scarborough Park. It’s full of big beautiful trees, but the major attraction for me is the pond in the middle, which is part of the ‘Wetland Highway’ that goes all the way to the Georges River at Sans Souci.
If you like nature & especially birds, anywhere along the Wetland Highway is a great place to wander. There is a lot of wildlife living here & although houses are close by, the surrounding trees & the naturalness allows you to feel as though you have left the madding crowd. It’s also quiet.
What we found was a floating pontoon secured to the banks by ropes, which appeared to be a coir mix planted with native grasses. This was so intriguing that I decided to call Rockdale Council to find out what it was & I am glad that I did.
The pontoon is a floating wetland designed to control & prevent algal blooms by consuming the excess nutrients that enter the pond through groundwater. Scarborough Park was built in the middle of what was once a rubbish dump. When it rains, groundwater seeps into the pond bringing with it nutrients that can result in algal blooms.
An algal bloom can completely cover a body of water, clogging the gills of fish & blocking sunlight from reaching underwater plants, which can result in their death. Decomposition of the algae produces bacteria that consumes much of the dissolved oxygen in the water. The lack of oxygen & plant die-off creates toxic water killing the fish, insects, other aquatic animals, as well as birds & other land animals. This is not what you want in any water system, particularly a prime area of biodiversity.
I think the floating wetland is a brilliant initiative. Not only will it help keep the pond clean & prevent algal build-up, but it also offers another place for waterbirds to perch to watch the water. The birds may not take up this opportunity in this location because there are lots of trees around the pond that have branches that cascade over the water, but for the Cooks River, there are very few places where tree branches reach over the water.
It would be great to see a few floating wetlands along the Cooks River, as the river has a massive nutrient polluton problem from stormwater entering the river. I also think it would be quite easy & cheap to modify a floating wetland to allow waterbirds a place to perch.
The floating wetlands not only have a positive impact on the health of the water & biodiversity, but also offer an educational opportunity to anyone that sees them. Rockdale Council placed their floating wetland in a section that was visible from a high traffic road, which resulted in us deciding to stop & look, as well a phone call to Council to learn more. I’d say that educational approach worked.