Stormwater Drainage Problems in Melbourne: Causes, Solutions and Who’s Responsible

Stormwater drainage problems in Melbourne usually come down to three things: water that can’t get away fast enough, pipes that have cracked or filled with roots, and confusion over who is actually responsible for fixing them. As a general rule, everything from your roof to the council’s drain is yours — and that surprises a lot of homeowners. Around The Clock Plumbing Pty Ltd, Oakleigh South, diagnoses and fixes stormwater faults across Melbourne’s south-east and Bayside, and this guide explains what causes them, how they get fixed for good, and exactly where your responsibility ends and the council’s begins.

What causes stormwater drainage problems in Melbourne homes?

Stormwater carries rain from your roof, paving and surfaces away to the public network. When it backs up or pools, the cause is almost always one of these:

Reactive clay soils. Much of the south-east sits on clay that swells and shrinks with moisture, slowly cracking older clay and earthenware stormwater pipes and pulling joints apart.

Tree-root intrusion. Roots find their way into pipe joints chasing moisture, then expand and trap debris. It is Melbourne’s most common drainage problem, and stormwater lines are just as vulnerable as sewers.

Undersized or aged pipes. Older systems were never sized for today’s intense summer downpours, so they surcharge and water surfaces in the yard or against the house.

Blocked pits and downpipes. Silted stormwater pits, leaf-choked downpipes and charged (pressurised) lines that have lost their seal all stop water moving.

Wrong fall. Pipes laid at the wrong grade — often poor original workmanship — let water pool instead of draining away.

Common warning signs are water pooling near the foundations or under the house after rain, pits that overflow in a downpour, damp brickwork, erosion along a boundary, and gurgling drains.

Stormwater or sewer: why the difference matters

Stormwater and sewer are two separate systems. Stormwater takes clean rainwater to the council or Melbourne Water network; the sewer takes wastewater from your toilets, sinks and showers to the sewerage system. It is against the rules to cross-connect them. The distinction matters because a stormwater problem — flooding, pooling, an overflowing pit — is handled very differently from a sanitary blockage or a sewage overflow, which is a health risk and a different repair altogether.

Who is responsible for stormwater drains — you or the council?

This is where most homeowners get caught out. Responsibility is split at a point called the legal point of discharge.

Your responsibility. You own and must maintain every stormwater pipe, pit, gutter and downpipe within your boundary — and the pipe that carries your stormwater out to the council’s nominated legal point of discharge. That often includes the section of pipe running under the nature strip or road reserve to the kerb or council drain. If it carries your water, it is generally yours to maintain.

The council’s (or Melbourne Water’s) responsibility. Beyond the legal point of discharge, the asset owner takes over — usually your local council for local street drainage, and Melbourne Water for larger regional catchments (generally those above about 60 hectares).

Overland flow. You must accept natural overland flow from neighbouring or public land, and you must not divert or redirect stormwater so it floods a neighbour. Water flooding a neighbour from a faulty private system is generally treated as a civil matter between owners, and you can be liable for the damage.

Your legal point of discharge is nominated by your council and was usually set by the building surveyor when the property was approved. These obligations sit under the Victorian Water Act 1989. For your property’s exact discharge point and rules, your local council or Melbourne Water is the authority to ask — this guide is general information, not legal advice.

How do you fix a stormwater drainage problem for good?

A cheap fix clears the symptom; a permanent fix finds and removes the cause. That is the difference between paying once and paying every wet season. Our approach is built around it: we arrive fast — often within the hour across the south-east — put a Ridgid CCTV drain camera (40–305mm) through the line to see exactly what is happening, then fix the actual fault rather than clearing it and leaving. Depending on what the CCTV inspection shows, the permanent fix might be:

Hydro-jetting to cut out roots, silt and debris and fully clear the line.

Pipe relining — sealing cracks and root-entry points from the inside with no-dig CIPP technology and a 35-year design life, often without digging up gardens, driveways or paths. We explain the choice in our guide to pipe relining versus replacement.

Re-laying or upgrading sections at the correct fall, installing new pits or subsoil (ag) drains, or increasing pipe capacity where the old system simply can’t cope.

When should you call a plumber about stormwater?

Call when water pools near or under the house after rain, when a pit overflows, when you notice damp or erosion, or when downpipes back up. If water is entering the subfloor or the home during heavy rain, treat it as urgent — it is one of the urgent issues worth acting on immediately. Acting early is the cheap option: stormwater damage to footings and foundations costs far more to repair than the drainage fault that caused it.

Common questions about stormwater drainage in Melbourne

Who is responsible for the stormwater drain in my nature strip?

You are. You are responsible for the stormwater pipe carrying water from your property to the council’s nominated legal point of discharge, including the section that runs under the nature strip or road reserve. Beyond that connection point it becomes the council’s or Melbourne Water’s. For your exact point of discharge, ask your local council.

Why does my backyard flood every time it rains heavily?

Usually an undersized, blocked or broken stormwater system — silted pits, root-filled or cracked pipes, leaf-choked downpipes, or pipes laid at the wrong fall. A CCTV camera inspection shows the actual cause so it can be fixed rather than guessed at.

Can stormwater pipes be relined instead of dug up?

Yes. Cracked or root-affected stormwater pipes can often be relined using no-dig CIPP technology, sealing the pipe from the inside with a long design life and no need to excavate gardens, driveways or paths.

Is a blocked stormwater drain an emergency?

It can be. If water is pooling against the building or entering the subfloor or home during heavy rain, treat it as urgent to protect the foundations and structure. We answer the phone 24/7 and can usually reach the south-east within the hour.

My neighbour’s stormwater is flooding my property — what can I do?

Stormwater flowing onto your land from a neighbour’s faulty or inadequate private system is generally a civil matter between owners, and your council usually cannot intervene. An independent written report identifying the source helps you resolve it; for overland-flow disputes, your local council can advise.

Written/reviewed by Christopher Unwin — founder, Around The Clock Plumbing Pty Ltd, Oakleigh South. BPC Licence #50694, Type A gas, 22 years experience. National Council member, Master Plumbers Association.

Updated May 2026