Leak detection on drains and sewers

Signs of a drain leak

• a stain that appears or grows after a particular appliance is used;
• sewer smells in a room or in the basement;
• damp at the foot of a downpipe or along a basement wall;
• slow drainage or recurring backflow;
• subsidence above a buried pipe.

Three complementary methods

• Fluorescein dye: the water from one appliance at a time is coloured, and we watch where it reappears. This tells us which appliance, which drain is at fault.
• Smoke testing: a non-toxic smoke sent into the system escapes through poorly fitted joints and cracks. Ideal for smells.
• CCTV inspection: we see inside the pipe, cracks, displaced joints, roots, deformation, back-falls.

Buried drains and sewer connections

Under a basement slab or in the garden, a cracked drain lets water soak into the ground and can, over time, destabilise it. CCTV inspection locates the defect by the length of cable run from the manhole, so digging happens only in the right place.