Stormwater is not the same as sewer drainage
Stormwater systems collect rain from roofs and hard surfaces. Sewer or sanitary drainage carries wastewater from toilets, bathrooms, kitchens and laundries. They are separate systems. If the overflow contains sewage, toilet paper or a strong wastewater odour, keep people and pets away and report it as a possible sewer overflow.
Common reasons a backyard drain overflows
- Leaves, soil, litter or roots restricting a grate, pit or pipe.
- A downstream pipe that is damaged, crushed, poorly graded or too small for the flow.
- Surface levels directing more water to one point than the system can receive.
- Roof, paving or landscaping changes that have increased runoff.
- A council or shared drainage issue beyond the property boundary.
- An extreme storm exceeding the design capacity of the local system.
What to do while it is raining
Keep clear of moving or deep water, submerged pits and any area near electrical equipment. Do not lift a heavy grate or enter a flooded pit. If it is safe from dry ground, note which grate overflows first, where the water travels and whether neighbouring properties or the street are affected.
Move loose belongings away from the flow path only if you can do so safely. Avoid creating a barrier that redirects water into a building or neighbouring property.
Do not wade into water to clear a drain. If water is entering the home, threatening electrical equipment or creating an immediate safety risk, contact the appropriate emergency service and keep people away.
Checks after the water falls
Photograph the overflow area and any visible debris. Note the rain intensity, approximate duration and whether the system drains down afterwards. From the surface, check accessible grates for leaves and loose debris, but do not reach into pits or use powered drain equipment.
Who is responsible?
Responsibility depends on where the restriction is located and who owns the asset. A private property drain is generally different from a council drain in the road or a shared owners-corporation system. A plumber can assess the private side and help identify whether the issue appears to continue beyond the boundary. The council, water authority or owners corporation makes its own responsibility decision.
What to include in your enquiry
- Whether the water is clear rainwater or appears contaminated.
- The first pit or grate that overflows.
- Whether it happens in every shower or only very heavy rain.
- Recent landscaping, paving, extensions or roof changes.
- Whether the street or neighbouring properties also flood.
- The suburb and safe access point to the affected area.
Stormwater help across the south east
The South East Plumber connects enquiries with independent providers across Melbourne's south east and the Mornington Peninsula. The provider confirms coverage, licensing, scope, timing and pricing before work begins.
See the stormwater plumbing service or share where and when the water rises.
Related plumbing services
Useful next steps: stormwater plumbing, blocked drain plumbing and drain cleaning.