Understanding Melbourne’s Stormwater System
Before we talk about fixing problems, it’s worth understanding how stormwater drainage actually works in Melbourne and who’s responsible for what parts of the system.
How Stormwater Flows
When rain hits your property, it follows a carefully designed path. Water runs off your roof into gutters and downpipes, flows onto your driveway, paths, and garden, enters your property’s stormwater drainage system, connects to council’s stormwater network through a legal point of discharge, and eventually reaches larger drains managed by Melbourne Water before flowing into creeks, rivers, and ultimately Port Phillip Bay.
This system is designed to move water quickly away from properties to prevent flooding and property damage. However, when any part of this system fails or becomes overwhelmed, problems cascade quickly.
The 60-Hectare Convention
Here’s something most Melbourne homeowners don’t know: responsibility for drainage is split between local councils and Melbourne Water based on the size of the catchment area. According to Water Victoria, since 1927, councils have managed smaller catchments (under 60 hectares) while Melbourne Water manages larger ones.
For your home, this means the City of Melbourne or your local council is responsible for kerb and channels (gutters), open channels, underground drains in public roads, and pits located in public areas. You, as the property owner, are responsible for all stormwater connections between your internal drainage system and the council’s network, including downpipes, pipes on your property, and connections to the legal point of discharge.
Need help understanding your property’s drainage requirements? Ezy-Plumb can assess your stormwater system and ensure compliance with council regulations. Call 0402 169 096 for expert advice.
Why Drainage Matters
If you think ‘it won’t happen to me,’ consider this: 13% of Victorians have experienced flooding multiple times since 2019, according to Climate Council researchcited by the City of Melbourne. Melbourne has a long history of significant flood events, including November 2010 when flash flooding in the CBD caused significant property damage, and February 2005 when riverine flooding caused widespread disruption to transport infrastructure.
Climate change is making things worse. Research shows that extreme short-duration rain bursts in Victoria are becoming more intense and more frequent, with a 14% increase already observed in the amount of rain falling during these events. The City of Melbourne’s drainage guidelines note that climate change effects are predicted to result in an 18.5% increase in rainfall intensity by 2100, combined with rising sea levels.
Our existing infrastructure wasn’t designed for these unnatural extremes. Gutters and stormwater drains designed for past conditions can quickly overflow, damaging roads, property, and other infrastructure. This makes proper maintenance and upgrades even more critical for Melbourne homeowners.
Common Stormwater Drainage Problems
Understanding what can go wrong helps you identify problems early, before they cause serious damage.
Blocked Stormwater Drains
This is by far the most common issue Melbourne homeowners face. Leaves, twigs, and debris from trees accumulate in gutters and drains, gradually reducing flow until water backs up. In Melbourne’s leafy suburbs, autumn can be particularly problematic as trees shed massive amounts of leaves that quickly clog drainage systems.
Signs of blocked stormwater drains include water pooling around downpipes or drains after rain, gurgling sounds from drains during heavy rain, overflow from gutters during moderate rainfall, damp patches or water stains on external walls, and water flowing onto neighbouring properties.
Tree Root Intrusion
Melbourne’s established trees are beautiful but problematic for drainage. Tree roots naturally seek out water sources, entering stormwater pipes through tiny cracks or joints. Once inside, they grow rapidly, creating massive blockages that can completely obstruct water flow.
Bayside suburbs like Brighton, with their heritage properties and mature gardens, are particularly prone to this issue. Warning signs include slow-draining gully traps, recurring blockages despite clearing, soggy patches in your garden with no obvious water source, and visible cracks or movement in paving near trees.
Damaged or Collapsed Pipes
Underground stormwater pipes don’t last forever. Age, ground movement, tree roots, and heavy vehicles driving over buried pipes can all cause damage. Terracotta pipes common in older Melbourne properties are particularly vulnerable to cracking and collapse.
You might notice water pooling in unusual areas of your property, sinkholes or subsidence in your garden or driveway, or recurring drainage problems that temporary fixes don’t solve.
Inadequate System Capacity
Some drainage systems simply weren’t designed for modern rainfall intensities. Properties built decades ago may have undersized pipes that can’t handle the volume of water from today’s more frequent intense downpours. This is especially problematic if you’ve added impervious surfaces like paved driveways or extended rooflines without upgrading your drainage.
Improper Connections
Surprisingly common are drainage systems where previous owners or contractors made incorrect connections. This might include stormwater connected to sewer lines (a serious code violation), downpipes discharging onto paving with no proper drainage, or connections that don’t reach the legal point of discharge.
According to the Victorian Building Authority, all stormwater systems must comply with the National Construction Code, and councils have the authority to require property owners to rectify non-compliant drainage.
Experiencing drainage problems? Don’t wait for water damage. Ezy-Plumb offers comprehensive stormwater assessments including CCTV inspections to identify issues before they become expensive disasters.
Solutions and Upgrades
When problems arise or better yet, before they do, several solutions can protect your property.
Professional Drainage Assessments
The first step in solving drainage problems is understanding exactly what you’re dealing with. Modern plumbers use CCTV cameras to inspect underground pipes, identifying blockages, damage, root intrusion, and structural issues without excavation. This technology allows precise diagnosis and targeted repairs rather than guesswork and unnecessary digging.
For Melbourne properties, particularly older homes in established suburbs, a drainage assessment every few years is excellent preventive maintenance. It’s far cheaper than emergency repairs after flooding.
High-Pressure Water Jetting
For clearing blockages, high-pressure water jetting is highly effective. This technique uses pressurised water (typically 3,000-4,000 PSI according to Australian standards) to blast through blockages and scour pipe walls cleanly. Unlike chemical cleaners or manual rodding, jetting completely removes accumulated debris and even cuts through tree roots.
The process is environmentally friendly, using only water with no harsh chemicals. It’s particularly effective for Melbourne’s common drainage problems like leaf buildup and tree root intrusion.
Pipe Relining
When pipes are damaged but not completely collapsed, relining offers a cost-effective alternativeto excavation and replacement. This trenchless technology involves installing a new pipe within the old one using epoxy resin. The relined pipe is stronger than the original, resistant to tree roots, and can last 50 years or more.
For Melbourne properties where excavation would mean tearing up established gardens, driveways, or heritage paving, relining is often the ideal solution.
Ready to upgrade your stormwater system? Ezy-Plumb designs and installs compliant drainage solutions for Melbourne properties. Book your consultation at Ezy Plumb.com.au or call 0402 169 096.
When to Call a Professional
Some drainage maintenance you can handle yourself - clearing visible debris from gully traps, hosing out downpipes, basic gutter cleaning if you’re comfortable working on ladders. But many situations require professional expertise.
Call Ezy-Plumb Immediately For…
Water pooling around your home’s foundations (this can undermine structural integrity), recurring blockages despite your clearing efforts, water backing up into your home, visible damage to drainage pipes or structures, water flowing onto neighbouring properties, sewage odours near stormwater drains (indicating potential cross-connection), or before major renovations or additions that affect drainage.
Professional plumbers have the equipment and expertise to properly diagnose problems, clear serious blockages safely, repair or replace damaged components, ensure compliance with regulations, and provide documentation for council or insurance.
The Cost of Delaying!
It’s tempting to put off drainage repairs, especially if problems seem minor. However, water damage escalates quickly. What starts as a small blockage can lead to flooding, foundation damage, mould growth, and structural issues costing tens of thousands to repair.
Melbourne Water’s research shows flooding impacts cost Victorians $735 million annually. Much of this is preventable with proper drainage maintenance. The few hundred dollars for professional drain cleaning or repairs is insignificant compared to potential water damage costs.
Stormwater drainage might not be the most exciting aspect of property ownership, but it’s one of the most important for protecting your Melbourne home from water damage. With flooding impacts costing hundreds of millions annually and climate change increasing rainfall intensity, proper drainage isn’t optional; it’s essential.
Don’t wait for water damage to discover your drainage isn’t up to the task. Whether you need a preventive inspection, emergency repairs, or system upgrades, professional help is just a phone call away.
