What is stormwater?
Stormwater is rainwater that falls on your roof and hard surfaces (driveways, paths, patios). A proper system collects, carries, and safely discharges that water to a legal point—either on-site disposal (like a soakage trench) or a council-approved street connection—so it doesn’t pool near your home, undermine footings, or flood living areas.
Key system components
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Gutters & downpipes
Collect water from the roof and feed it into below-ground drains. Correct sizing and fall are essential for heavy downpours.
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Surface drains
Grated channels or pits catch runoff from driveways, patios, and paths before it can enter the home.
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Pits & inspection points
Access points that allow cleaning, debris capture, and changes in direction or depth.
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Underground pipework
Carries water to the disposal point. Older homes may have earthenware that can crack and allow roots; modern systems use durable PVC.
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Soakage trenches & sumps
On-site disposal options that allow water to percolate into suitable soils; sumps can also collect and redistribute flow.
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Legal point of discharge
The approved endpoint—usually a council connection at the kerb or a shared system—where stormwater can leave your property.
How a system moves water
- Capture: Roof runoff enters gutters and downpipes; surface drains collect water from hardstand areas.
- Convey: Water flows via underground pipes, assisted by gravity and adequate pipe fall.
- Manage debris: Pits and grates intercept leaves and sediment to prevent blockages.
- Discharge: Water exits at the legal point (street connection) or percolates via soakage where appropriate.
- Overflow planning: Good designs include contingency paths so extreme rainfall doesn’t backflow into structures.
Adelaide conditions & design choices
Adelaide’s geography ranges from sandy coastal soils to clay-dominant foothills. Design choices depend on soil type, site slope, roof area, and local rules:
Coastal & western suburbs
Sandy soils drain quickly but can shift. Robust strip drains and sumps, plus stable bedding, help prevent movement.
Foothills & eastern areas
Clay soils have slower infiltration, so soakage must be carefully sized. Surface drainage and controlled discharge are common.
Hills & sloping blocks
Runoff moves fast down gradients; retaining wall drainage, terraces, and channels protect structures and landscaped areas.
Inner suburbs & tight access
Older pipes and limited access need smart staging and often CCTV to plan targeted, minimally invasive repairs.
All systems should be installed to relevant standards and council conditions, with documentation provided at handover.
Signs of trouble
- Pooling around the house, driveway, or low garden beds after rain
- Gurgling drains, slow runoff, or surcharge from grates
- Damp patches along known pipe runs; sinking pavers or garden areas
- Overflowing gutters or downpipes during heavy rain
- Musty smells or dampness on internal walls adjacent to external drains
How professionals diagnose issues
- Site assessment: Check roof area, catchment, falls, and likely pinch points.
- CCTV inspection: Identify blockages, root intrusion, and collapses without excavation.
- Hydraulic reasoning: Ensure pipe sizes and gradients handle peak flows.
- Plan & quote: Provide options (repair vs replacement), compliance steps, and timelines.
Common solutions we use
Targeted repairs
Replace only failed sections—common for root-affected earthenware—to restore flow quickly and cost-effectively.
Full PVC upgrades
Modern, durable pipework with correct falls and inspection access to future-proof your system.
Surface drainage
Strip drains, grated channels, and pits to intercept water at driveways, patios, and pathways.
Soakage & sump solutions
Sized for soil type and roof area; sumps can include pumps where gravity discharge isn’t possible.
Typical cost factors
Exact pricing depends on site access, length and depth of pipe runs, materials, restoration, and whether approvals are needed. Expect variation for:
- Pipe length, depth, and number of pits/inspection points
- Soil type and required bedding/backfill (sandy vs clay)
- Driveway/paving removal and reinstatement
- Street connection vs on-site soakage sizing
- CCTV time, excavation method, and spoil removal
We provide clear, itemised quotes and can stage works to suit your budget and timeline.
Maintenance checklist
- Clear gutters and downpipes before wet months
- Keep grates and strip drains free of leaves and mulch
- Watch for new pooling patterns after heavy rain
- Schedule CCTV if you suspect roots or collapse
- Trim trees whose roots target older earthenware
- Review overland flow paths & contingency overflows
FAQs
What’s the difference between stormwater and sewer?
Stormwater is rain runoff from roofs and hardstand areas; sewer carries household wastewater. They are separate systems with different rules and endpoints.
How do I know if my stormwater is blocked or collapsed?
Pooling, slow drains, damp patches, or overflow during rain are common signs. A CCTV inspection pinpoints the cause.
Do I need council approval?
Some works—particularly street connections—require compliance with council conditions and relevant standards. We’ll advise during quoting.
How often should I maintain the system?
Seasonally, and after major storms. Mature properties or leafy blocks may need more frequent checks.
Need help with stormwater at your place?
We diagnose, design, install and repair systems across Adelaide.