Insights · 29 January 2026 · Planted
The City of Sydney is filtering stormwater with rain gardens at Sydney Park and Green Square. New research shows most councils still don't lock in the maintenance that keeps WSUD assets working.
The City of Sydney is putting real money into water-sensitive infrastructure - stormwater recycling at Sydney Park and Green Square, and rain gardens built into streetscapes to filter runoff before it reaches the Cooks River. It’s the right direction. But a recent review of council stormwater guidelines across Australia found the weak point isn’t building these assets - it’s keeping them working.
The asset is the easy part
The research is blunt about it: enforceable maintenance provisions showed up in only about a fifth of the council documents reviewed. In other words, plenty of WSUD goes in the ground, but far fewer jobs lock in who keeps it functioning afterward. A rain garden or bio-retention system that isn’t maintained silts up, weeds over and stops filtering - it becomes landscaping that happens to be wet.
What keeps WSUD planting doing its job
- Install it right. Mesh first on infiltration zones, the correct profile, planting matched to the wet-and-dry cycle the system actually sees.
- Establish the planting. A bio-retention bed only works once the vegetation is established and doing the filtering. That’s a maintenance window, not a planting day.
- Keep the weeds and silt out. The two things that quietly kill a rain garden. Ongoing maintenance is the difference between a working asset and a blocked one.
The takeaway
WSUD is only as good as its upkeep. The councils building rain gardens are doing the right thing - the gap to close is making sure the planting is installed properly, established, and maintained so the asset still works in five years.
That’s the work we do on erosion control and WSUD planting across NSW, install-only or supplied and installed. Got a rain-garden or infiltration job? Tell us about it.
