Caution
The pan fills and drains slowly, or does not drain at all, and a second flush makes it worse.
High risk
Water or sewage is standing in an outside gully or inspection chamber and rising instead of draining away.
A foul sewage smell around an outside drain, a downstairs room or an appliance, with nothing visibly blocked.
A sink, bath or toilet gurgles when something else drains: air is being dragged through a trap.
Emergency
Foul water is rising into the lowest fitting in the house because the drain below it is completely blocked.
The grated drain outside the kitchen or bathroom wall is full and slow, and water pools around it.
The same run blocks again every few months, and what comes out is fibrous rather than what was flushed.
The drain blocks constantly, the ground has sunk above it, and jetting only buys a few weeks.
The large vertical waste pipe on the wall is wet, stained or dripping when a toilet upstairs is flushed.
Gullies, chambers or the garden flood every time there is a downpour, then clear once the rain stops.
Describe the job and get a fixed price from a local drainage engineer.
