If you suspect tree roots in a drain, get a CCTV inspection and professional clearing done first. Relining or repair only follows once a plumber confirms whether the pipe itself is structurally compromised. Stop DIY attempts and call a licensed plumber immediately if you see sewage backflow, repeated blockages within weeks of each other, or sudden sinkage in the yard above the pipe run.
TL;DR:
- Repeated drain blockages often indicate a cracked or deteriorated pipe, and a CCTV inspection is crucial before choosing to clear or repair.
- Root intrusion typically exploits existing pipe weaknesses, meaning a structurally sound pipe resists roots almost entirely, especially if well-sealed.
- Mechanical cutting provides immediate relief but does not prevent regrowth; combining it with relining or replacement offers a long-term solution.
- Property trees such as eucalypts, figs, or willows planted near underground pipes significantly increase the risk of root intrusion in shallow or aging pipes.
- Routine inspection and targeted repairs, including relining, can reduce long-term costs and prevent recurring problems caused by root-related pipe damage.
Table of Contents
- How do tree roots get into drains and cause blockages?
- What are the warning signs of roots in your drains?
- Removal methods: what actually clears roots from pipes?
- Long-term fixes: relining, replacement and prevention
- How much does root removal cost and how long does it take?
- What Priority Plus Plumbing looks for on a callout
- A plumber’s brief perspective: how to avoid repeat problems
- Get a CCTV inspection before the next blockage hits
- Sources
- FAQ
How do tree roots get into drains and cause blockages?
Tree roots in drains are one of the most common causes of recurring blockages in older homes, and the pattern is rarely random. Roots don’t force their way through solid pipe. They exploit weaknesses that already exist, following moisture vapour escaping through hairline cracks, loose joints, or degraded seals until a fine root tip finds its way in and thickens over months or years.
That distinction matters for how you fix the problem. Research from the US Forest Service shows tree roots exploit cracks and joints rather than creating them, meaning a root intrusion is usually a symptom of a pre-existing pipe fault, not the original cause. NC Cooperative Extension confirms the same mechanism: intact, well-sealed pipe resists roots almost entirely.
Certain pipes are far more vulnerable than others:
- Older clay or concrete pipes with mortared or rubber-ring joints that degrade over decades
- PVC or poly pipe with poorly glued or shifted joints, often from ground movement
- Shallow pipe runs (under 60cm) near established trees with aggressive root systems
- Properties with large eucalypts, figs, or willows planted within a few metres of the sewer lateral
Once a root gets a foothold, the damage progresses in stages. A few fine roots create a partial blockage that catches wipes and grease. Left alone, the root mass thickens, pipe joints separate further under the pressure, and the pipe can crack or collapse outright, sometimes contaminating the surrounding soil with sewage. Tree distance and species matter, but as CSU research on stormwater and sewer systems points out, pipe condition is usually the deciding factor, not how far away the tree sits.
What are the warning signs of roots in your drains?
Tree root damage rarely announces itself with a single dramatic event. It builds slowly, and the early signs are easy to write off as one-off nuisances.
Watch for this pattern of symptoms:
- Slow-draining sinks, showers, or toilets in more than one part of the house at the same time
- Toilets that gurgle or bubble when a nearby tap runs or the washing machine drains
- A persistent sewer smell near the yard, especially after rain
- Unusually lush, green patches of grass or garden growth directly over the pipe run
- Sudden weed or plant growth pushing up through a drain grate or inspection point
The giveaway is the pattern, not any single symptom. A blocked kitchen sink on its own is probably grease or food scraps. Slow drainage in the bathroom, laundry, and kitchen all at once, especially if it keeps returning after you clear it, points to a shared line problem further down, most likely the sewer lateral running from your house to the street main. If you’ve cleared the same drain twice in a few months, that’s not bad luck. It’s a sign the root mass is regrowing faster than a plunger or a bottle of drain cleaner can keep up with, and it will keep getting worse until someone deals with the pipe itself.
Removal methods: what actually clears roots from pipes?
There’s no single fix that suits every root problem, and picking the wrong one can cost you more in the long run. Here’s how the main options stack up.
- Mechanical cutting (auger or root saw). A motorised cutting head chews through the root mass and restores flow almost immediately. It’s fast, relatively cheap, and often the right emergency measure when a fixture won’t drain at all. The catch: it doesn’t touch the crack or joint the root grew through, so regrowth is common within months. Combining a cut with a plan for structural repair is the only way to break that cycle, a point backed by the Forest Service’s cost review.
- High-pressure water jetting. A jetting nozzle blasts water at several thousand PSI through the pipe, stripping root fibres, grease, and sludge from the walls rather than just punching a hole through the middle. It’s usually more thorough than an auger and leaves the pipe cleaner, but jetting alone still won’t repair a cracked pipe or failed joint underneath the root mass.
- Chemical root killers and foaming treatments. Products containing dichlobenil or foaming, salt-based herbicides can slow regrowth for a while after mechanical clearing. Homeowner forums, including discussion on the Bunnings Workshop community, often recommend these as a follow-up step, but they’re a temporary measure at best. Overuse can also affect surrounding soil and nearby plants, and none of these products repair the pipe defect that let roots in to begin with.
Pro Tip: If you’ve had the same drain cleared more than twice in twelve months, stop paying for repeat clearing and ask for a CCTV inspection instead. Repeated cutting without fixing the underlying crack is money spent treating the symptom, not the cause.
Industry guidance on clearing sequences, including from trade resources like Nuflow, consistently follows the same order: inspect first, clear second, then assess whether the pipe needs relining or replacement. Skipping straight to chemicals or a DIY auger without ever seeing what’s happening inside the pipe means you’re guessing at a problem a camera could show you in minutes.
Long-term fixes: relining, replacement and prevention
Clearing a blocked drain buys you time. It doesn’t fix a cracked pipe or a failed joint, and if that’s the real problem, the roots will be back.
Pipe relining is a no-dig repair where a resin-coated liner is inserted into the existing pipe and cured in place, forming a new, jointless pipe inside the old one. It’s the standard fix once a CCTV inspection confirms root intrusion through a crack or separated joint rather than a full collapse. A well-installed relined pipe can last decades without needing to be dug up, and because there are no joints for roots to exploit, it’s far more resistant to repeat intrusion than the original jointed pipe.
Full replacement is usually reserved for pipes that have collapsed, sagged out of grade, or suffered damage along too much of their length to reline effectively. It’s more disruptive and costs more upfront, but it’s the only real option once a pipe is structurally beyond repair.
Beyond the pipe itself, a few practical steps reduce the odds of ever getting to that point; for detailed prevention advice, see Tree roots in your sewer line: fix it for good.
- Install root barriers around the sewer line when planting new trees near the property boundary
- Choose smaller, less invasive species for garden beds close to pipe runs, rather than large eucalypts or figs
- Remove or relocate problem trees where roots have already caused repeat intrusions
- Book a CCTV check every couple of years if you’ve had root problems before, rather than waiting for the next blockage
Predictive, inspection-led maintenance consistently comes out ahead of reactive clearing in the research, including a 2025 review in Sustainability that found scheduled inspection and targeted repair reduce long-term costs compared with fixing things only after they fail.
How much does root removal cost and how long does it take?
A CCTV inspection is the logical starting point for almost any drain problem, and it’s worth treating as an investment rather than an added expense. It shows exactly where roots have entered, how bad the damage is, and whether you’re looking at a simple clear or a structural repair, which means you’re pricing the actual job instead of guessing.
Root intrusion is responsible for more than half of all sewer blockages in some reviews of sewer system failures, and reactive root removal can run at roughly one-sixth the cost of full pipe replacement, which is exactly why catching the problem early with an inspection matters so much.
Rough guide to what each stage typically involves:
- CCTV inspection: usually completed within the hour, giving you a clear picture before any clearing work starts. See our CCTV inspection cost guide for what affects the price.
- Jetting or auger clearing: typically a same-day job once the blockage location is confirmed.
- Pipe relining: usually completed in a day for a standard residential lateral, though access and pipe length affect the timeline.
- Full replacement: can take several days, particularly where excavation, council permits, or difficult access near established trees are involved.
Costs climb with pipe depth, how hard the pipe is to access, proximity to large trees, and whether council permits are needed for work near a street tree or public sewer main. If you’re deciding between clearing now and monitoring, or committing to relining straight away, the deciding factor is usually how many times the same section has already blocked. Once it’s happened twice, ongoing clearing rarely stays the cheaper option for long.
What Priority Plus Plumbing looks for on a callout
Priority Plus Plumbing has spent more than 25 years responding to blocked drains and sewer problems across Sutherland Shire and Sydney, running a 24/7 emergency service built around CCTV-first diagnostics, upfront pricing, and a workmanship guarantee on every job.
Before a plumber arrives, a few things speed up the visit:
- Note which fixtures are affected and when the problem started
- Take a photo of any unusually green or wet patches in the yard above the suspected pipe run
- Have any past plumbing invoices or drain history on hand, especially if this isn’t the first blockage
The sequence stays the same on almost every root job: CCTV inspection first, then jetting or clearing to restore flow, then an honest conversation about relining if the camera shows structural damage, followed by a maintenance schedule to catch any regrowth early.
A plumber’s brief perspective: how to avoid repeat problems
The homeowners who spend the least on drains over the years aren’t the ones who never get roots. They’re the ones who fix the pipe the first time instead of clearing the same blockage every winter. We’ve seen jobs where a kitchen sink kept backing up every few months for two years, always cleared with a quick auger run, until a CCTV camera finally showed a root mass growing through a cracked joint six metres down. Relining that section fixed it permanently, and it cost less than three more years of callouts would have.
— Peter Honey
Get a CCTV inspection before the next blockage hits
You’ve seen how tree roots exploit existing cracks and joints rather than causing brand-new damage, which is exactly why guessing your way through repeated clearing rarely solves anything for good. Priority Plus Plumbing takes the opposite approach: every root job starts with a CCTV inspection so you know precisely what’s happening in the pipe before any work begins, backed by upfront pricing and a workmanship guarantee on the repair.
On a callout, expect a plumber to run the camera first, walk you through what it shows, and quote clearing, jetting, or relining based on the actual condition of the pipe, not a guess. If you’ve had the same drain blocked more than once, it’s worth booking a CCTV inspection rather than paying for another clear that won’t hold. Get in touch with Priority Plus Plumbing to arrange an inspection and find out exactly what’s happening under your yard, available around the clock for genuine plumbing emergencies.
Sources
The US Forest Service’s review of root intrusion covers the extent and cost of the problem across sewer systems. NC Cooperative Extension explains the crack-and-joint mechanism in plain terms. Sustainability’s 2025 review makes the case for predictive maintenance, while council guidance and Queensland’s plumbing laws clarify homeowner responsibility and when licensed trades are required.
- Tree root intrusion in sewer systems: A review of extent and costs | US Forest Service
- Tree roots and sewer lines | NC Cooperative Extension (Union County)
FAQ
What dissolves tree roots in drains?
Foaming, salt-based herbicides and dichlobenil-type products can slow regrowth after a drain has been mechanically cleared, but nothing dissolves a mature root mass on contact, and these treatments don’t fix the underlying pipe crack.
What dissolves tree roots in sewer lines from a hardware store?
Hardware-store foaming root killers work the same way as trade products, slowing regrowth after clearing rather than removing an existing blockage, and they’re a temporary measure rather than a permanent fix.
Who is responsible for tree roots blocking drains?
Homeowners are generally responsible for the private sewer lateral running from the house to the property boundary, while councils typically manage the section from the boundary to the street main; check your local council guidance for specifics.
How can I remove tree roots from my drains?
A licensed plumber typically runs a CCTV inspection first, clears the roots with jetting or a mechanical auger, then assesses whether the pipe needs relining or replacement to stop roots returning.
When should I call a plumber instead of trying it myself?
Call a plumber immediately if you see sewage backflow, the same drain blocks more than once in a few months, or the yard above the pipe shows sudden sinkage, since these usually signal structural pipe damage that DIY methods can’t fix.