A blocked drain that keeps coming back is rarely bad luck. Often, a tree root has found a crack in an old pipe. Here's what fixes it.
KEY TAKEAWAYS
Tree roots cause about one in three wastewater pipe blockages and overflows, according to Queensland utility Unitywater. Roots rarely break into a sound pipe. They find a crack or loose joint, follow the moisture escaping from it, and grow in. Once inside, a root thickens and traps debris until the flow stops.
Water Corporation warns that roots can rupture water pipes and creep into wastewater lines. Older clay pipes are most at risk, especially during Perth's wet winter.
Root intrusion builds slowly, so the early signs are easy to dismiss. Of Unitywater's 1,300 callouts, 439 involved roots, some ending as sewage overflows into homes. Catch it early and you're paying for a camera inspection rather than a sewage cleanup.
Start with a plumber, not a chainsaw. A CCTV drain camera confirms whether roots are the problem and where they got in; the plumber cuts or jets them out and repairs or relines the cracked section. Skip the repair, and the roots grow back through the same gap.
If the same tree keeps invading the line, removal plus stump grinding stops regrowth. See what happens to roots after stump grinding and removing big tree roots.
Distance is your best defence. Water Corporation's guidance is to plant trees at least 0.5m from water assets and 2.7m from the property boundary line. Before planting, request free service plans from Before You Dig Australia so you know exactly where the pipes run.
Unitywater lists willows, gum trees and camphor laurels among the worst offenders; Water Corporation's waterwise list favours low-invasive roots. A root barrier can protect pipes from an established tree.
