Our biggest stormwater recycling system yet!
As part of our commitment to conserving water, Randwick City Council has built our biggest stormwater harvesting system ever! This project, which was built in 2020, is underground at Maroubra Beach and is our 14th stormwater harvest system. The system will save up to 40 million litres of potable water every year, as well as financial savings. You can watch this video about how it works, hosted by Tim Silverwood.
How does it work?
When it rains, water flows along our roads and gutters and enters the stormwater system through drains. Usually the water continues to flow through drains and gutters, exiting the stormwater system through a drain into the ocean. To harvest the stromwater, we redirect it, then capture so we can use it to keep our parks and reserves green. Yet, before it's used for watering our parks, we filter it to ensure it's as clean as possible.
The first step is to send the water through the gross pollutant trap (GPT). This spinning vortex removes large debris and pollution. The GPT we use in Maroubra is located underground on the corner of McKeon Street and Marine Parade.
You can watch a video about how GPTs work here:
From the GPT the water is flows into a seven-metre deep pump well, on the opposite side of the road, across from the GPT that's buried under the grass and looks like this:
Inside the pump well, submergible pumps pump the water at 30 litres per second through pipes that have been laid under the ground all the way to Arthur Byrne Reserve, where it enters the first one-million litre underground storage tank.
Below is a photo of the two one-million litre stormwater harvesting tanks, which we've constructed and buried under Arthur Byrne Reserve. The water moves along the pipes into the first one, where it goes through a fine sediment filtration system. Then, the water moves into the second underground storage tank, where it is topped up with bore water to boost supply if needed.
So, what's happening underground? Watch this animation to find out.
When the water is ready to use, it's pumped through a UV filtration system, which removes any viruses or pathogens before it is sent through underground pipes to irrigate the following reserves:
- Arthur Byrne Reserve
- Broadarrow Reserve
- Jack Vanny Reserve
- Maroubra Beach
- John Shore Reserve (future irrigation system to be installed)
- Murranborah Reserve (future irrigation system to be installed)
It will also provide water for the toilets at Maroubra Surf Club and South Maroubra amenities, once complete. The system will save up to 40 million litres of potable water every year, as well as financial savings that come with not having to buy water from Sydney Water. To learn more about the building of this project, see the project page.
Want to know more?
For students or those who are just curious, if you'd like to see more of the fine detail involved with this project, the following documents may help.