AustraliaWho is responsible for stormwater drainage between neighbors in Australia?
In Australia, landowners are generally responsible for stormwater runoff from their property. They must not unreasonably interfere with natural drainage or divert water onto a neighbour’s land.
What the Law Says
Australian stormwater law is primarily state-based, rooted in common law principles of nuisance and riparian rights, supplemented by statutory water management frameworks.
Under common law, landowners have a 'natural right' to receive surface water that flows onto their land in its natural course — but no right to artificially increase or alter that flow onto a neighbour’s property. This principle was affirmed in the High Court case *Halsey v. Esso Petroleum Co Ltd* (1961) 105 CLR 427, which upheld that altering natural drainage may constitute private nuisance.
Each state has specific legislation: In New South Wales, the *Water Management Act 2000* (NSW) s. 123 prohibits causing 'unreasonable interference' with natural water flow. In Victoria, the *Water Act 1989* (Vic) s. 36A makes it an offence to divert stormwater in a way that causes material damage to another’s land.
Queensland’s *Water Act 2000* (Qld) s. 448 similarly prohibits actions that 'unreasonably interfere' with another person’s lawful use of water. Courts consistently hold that responsibility lies with the upstream landowner if they install impermeable surfaces, pipes, or grading that increases volume, speed, or direction of runoff onto adjacent properties.
Statutory TextA person must not unreasonably interfere with the natural flow of water across land.
— Water Management Act 2000 (NSW), s. 123(1)
Statutory TextIt is an offence to divert stormwater in a manner likely to cause material damage to another person’s land.
— Water Act 1989 (Vic), s. 36A(1)
What to Do
Talk to your neighbour calmly and in writing — outline the issue and request remediation within 14 days.
Engage a qualified surveyor or hydraulic engineer to prepare a drainage report confirming flow patterns and liability.
If unresolved, lodge a dispute with your state’s civil and administrative tribunal (e.g., NCAT in NSW, VCAT in Victoria) — filing fees start at $54.
Seek mediation via your local Community Justice Centre (free or low-cost; available in all states).
As a last resort, consult a solicitor about seeking injunctions or damages under nuisance or statutory claims.
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Not legal advice. This article is general information based on publicly available sources, written for educational purposes. Laws change and individual situations vary. Consult a licensed attorney in your jurisdiction before acting on anything you read here. Last reviewed: 2026-10-11.